
The yen has been depreciating against the dollar and other currencies for several months. It fell from 100 yen = $0.97 in January 2021 to $0.61 by the end of July 2026 – a fall of 37%. This marked a 40-year low. But then, at the end of July it rallied and by 3 August the rate was 100 yen = $0.64 – a rise of nearly 5%. But why did this happen and what will be the implications for Japan and the wider world economy?
Why has the yen fallen so much since 2021?
There have been two main drivers.
The first is fiscal policy. For many years, Japan has been pursuing expansionary fiscal policy in an attempt to stimulate the sluggish economy. This has led to large budget deficits and public-sector debt. Since 2020, general government gross debt has been around 255% of GDP, the largest of any high-income economy.
Recently, the Japanese government has adopted aggressive supplementary budgets to fund, among other things, fuel subsidies and public-private investment initiatives. This has involved the issuance of more government bonds to fund the necessary borrowing.
Fiscal pressures have also increased becase of demography. A rapidly aging population and declining birth rates have required substantial public spending on healthcare, social security and pensions. Meanwhile, the tax-paying working-age population has declined as a proportion of total population.
On the plus side, unlike most highly indebted nations, over 90% of Japan’s debt is held domestically by Japanese residents, Japanese institutional investors, banks and the Bank of Japan (BoJ). This lowers the risk of default and hence the risk premium on Japanese bonds.
The second driver is monetary policy. Interest rates have been kept low over many years, including periods of negative rates, as the BoJ has attempted to stimulate the economy. Low interest rates have sometimes been backed up with quantitative easing to increase money supply.
Since March 2024, however, there have been four interest rate increases. The latest was in June 2026 when the BoJ raised the short-term policy rate from 0.75% to 1.0% – the highest level since 1995. Despite this, interest rates have remained below those in other countries, and this contributed to the continuing fall of the yen.
A falling yen has helped to increase Japanese exports by making them more competitive, but more expensive imports have contributed to rising Japanese inflation.
Low interest rates have also stimulated the yen-dollar carry trade. This is where investors borrow money in yen at low interest rates, convert it into US dollars and invest it in higher-yielding US assets, typically US government bonds (‘Treasury bonds’). This borrowing in yen to buy dollars further contributed to the depreciation of the yen against the dollar.
Co-ordinated intervention
In an attempt to raise the value of the yen, the Bank of Japan and the US Federal Reserve acted together – their first joint currency rescue operation since 2011. The BoJ spent tens of billions of dollars to buy yen; the US Treasury bought yen by selling euros. Prior to the intervention, global hedge funds held near-record short positions against the yen, meaning that they sold yen at a current price, agreeing to buy them back at a particular later date, hoping that the yen would fall in the meantime and that they would therefore make a profit. The sudden joint intervention forced these traders to buy back the yen to cut their losses before the rate rose further. This accelerated the yen’s appreciation.
But why did the USA join Japan in intervening? Japan is the largest foreign holder of US Treasuries ($1.1 trillion). The USA intervened to discourage Japanese investors from selling US Treasuries in order to raise cash, thereby pushing up US borrowing costs.
The rise in the yen was also encouraged by speculators who are expecting further interest rate rises from the BoJ to counter inflation and support public finances, driving domestic bond yields higher. This will lead to a narrowing of interest rates between Japan and other countries.
Effects on the Japanese economy
If the yen continues to appreciate, this will help to reduce inflation by making imports cheaper and will help to ease cost-of-living pressures on Japanese consumers. Japan is heavily reliant on imported energy and raw materials.
However, the decline in the yen over recent years has provided a large boost to Japanese exports. A sharp reversal in this could severely affect exporters’ profits and have a serious negative impact on economic growth.
If the appreciation continues, it would lead to an unwinding of the carry trade. To prevent mounting currency losses, highly leveraged institutional investors would be forced to sell assets, such as US and other countries’ shares and bonds to buy back yen and pay off their debts. This potentially massive unwinding would be likely to create global market volatility and drive up interest rates.
Articles
- Yen holds gains after Japan, US confirm joint intervention, signal more action
Reuters, Makiko Yamazaki and Leika Kihara (3/8/26)
- Yen surges to three-month peak, dollar pares losses after intervention
Reuters, Chibuike Oguh (3/8/26)
- US dollar weakens sharply against the Japanese yen after officials intervene in markets
ABC7 Eyewitness News, Mayuko Ono and Elaine Kurtenbach (3/8/26)
- Yen hits three-month high after Trump helps prop up currency
The Guardian, Graeme Wearden (3/8/26)
- Why has Trump stepped in to prop up Japan’s currency?
The Guardian, Jonathan Yerushalmy (3/8/26)
- Why the U.S. stepped in after decades to prop up Japan’s yen — and what’s at stake
CNBC, Lee Ying Shan (3/8/26)
- Politics & Policy Analysis: How Bessent is pushing Warsh’s Fed to expand backstop for Japan’s yen defense
CNBC, Matt Peterson (3/8/26)
- Why Japan is propping up the yen – and why the US helped
The Straits Times (4/8/26)
- The Pros and Cons of a Strong Dollar
Johnston Investment Counsel (3/8/26)
- Why the U.S. Stepped In to Prop Up Japan’s Yen Currency
Yahoo!Finance, Tiago Ventura (3/8/26)
- Why the U.S. Is Helping Prop Up Japan’s Weak Currency
The New York Times, Eshe Nelson (3/8/26)
- U.S.-Japan Intervention Triggers Yen Carry Trade Fears
The Chosun Daily, Lee Hai-woon (3/8/26)
- What top minds in markets are saying about the US intervention to prop up Japan’s currency
Business Insider, Jennifer Sor (3/8/26)
Data
Questions
- What have been the benefits and costs to Japan of a depreciating exchange rate?
- Explain the carry trade.
- Why might the yen-dollar carry trade unwind and what would be the consequences for Japan and the USA?
- Find out what has happened to the exchange rate between the yen and the euro. Has this been driven by the carry trade?
- For what reasons might the yen (a) now continue rising; (b) resume depreciating?
- Find out what has happened to the yen/dollar exchange rate since this blog was written. Explain your findings.
With relentless bombing of Iran by Israel and the USA, and with Iranian counterattacks on Gulf states, the costs of the war are mounting. The most obvious are in terms of human lives, injuries and suffering. But there are significant economic costs too. Some of these are immediate, such as the rising price of oil and hence the costs of fuel, or the fall in stock market prices. Some will be longer term, depending on how the war develops. For example, prices could rise more generally as supply chains are disrupted.
The impacts will vary across the world and across markets. The most obvious markets to be affected are those where significant supply comes from the Persian Gulf. Approximately 20% of total global oil consumption passes through the Strait of Hormuz, which connects the Persian Gulf with the Arabian Sea and the Indian Ocean.
Oil prices rose considerably in the days following the start of the war on 28 February, with Brent crude, a key measure of international oil prices, rising from $71.3 on 27 February to a peak of $119.4 per barrel by the morning of 9 March – a rise of 67%. It was possible that they would rise even further in the short term. However, prices fell back substantially later on 9 March after G7 finance ministers declared that the group ‘stands ready’ to release oil from strategic reserves if needed. By late in the day, the price had fallen to below $85. (Click here for a PowerPoint of the chart.)
However, despite the announcement on 11 March that 32 countries had agreed to release 400m barrels of oil reserves, oil prices began rising again and reached $100 on 12 March after three tankers had been struck in the Gulf, two of them close to the Strait of Hormuz. With Iran pledging to keep the Strait closed, there were worries that the release of oil reserves would provide only temporary relief. Just over 20m barrels of oil normally pass through the Strait of Hormuz. The 400m barrels released from storage is the equivalent, therefore, of only 20 days’ worth of lost oil from the Gulf.

Not only did oil prices rise, but the price became much more volatile as markets reacted to the news on a continuous basis. Intra-day fluctuations in oil prices of several percentage points became typical, reflecting shifting expectations. The second chart shows daily fluctuations, with the highest and lowest prices for each day shown, along with the closing price. (Click here for a PowerPoint.)
The biggest fluctuation had been on 9 March when fears of the closing of the Strait of Hormuz saw the price of Brent crude rising to nearly $120 but falling to around $84 later in the day (a fall of around 30%) after the G7 announcement about releasing reserves.
There was another big fluctuation on 23 March. The previous day (Sunday), President Trump threatened to bomb Iran’s power plants if Iran did not allow free passage of ships through the Strait of Hormuz. Iran threatened to retaliate by striking Gulf countries’ energy and water systems. In early trading on Monday 23rd, Brent crude rose to over $115 per barrel. But later that day, Trump said that there had been constructive talks between the USA and Iran. The oil price immediately dropped to around $96 – a fall of 17% – before settling at around $100.
Rising oil prices will drive up inflation. For those countries with a heavy dependence on Gulf oil, particularly countries in Asia, there could be significant supply problems. For oil exporters in the Persian Gulf, with tankers unable to traverse the Strait of Hormuz, the economic impact is huge. Oil exporters outside the Gulf, such as Russia, Norway and Canada, however, will gain from the higher prices. Clearly the size of these effects will depend on how long the conflict continues and how long the Strait of Hormuz remains closed.
And it is not just oil that is affected. Other products, such as liquified natural gas (LNG), petrochemicals, industrial materials, fertilizers for food production, medicines, helium for microchip production, metals and minerals are transported through the Strait of Hormuz. Gulf countries import much of their food through the Strait. On 18 March, Israel struck Iran’s huge South Pars gas field off the Gulf coast. This is the largest gas field in the world and is a major source of export revenue for Iran. Iran responded by striking the Qatari gas hub in Ras Laffan. Donald Trump responded by threatening to ‘blow up’ the entire Iranian South Pars gas field if Iran made further strikes on Qatar. The effect of this escalation was to drive oil and gas prices up further. By the week ending 20 March, the oil price closed at just over $112 per barrel.
Cuts in supplies of oil and other products represent an adverse supply shock. Such shocks push up prices (cost-push inflation), while adversely affecting aggregate output. This can lead to stagflation – a combination of higher inflation and stagnation or even falling output. Central banks with a simple mandate to keep inflation to a target are likely to raise interest rates, or at least delay in reducing them. In the USA, with a dual mandate of controlling inflation but also maximising employment, the response may be less deflationary, depending on the judgement of the Federal Reserve.
Uncertainty
There is great uncertainty about how long the conflict will last. There is also a lack of clarity and consistency from the US administration about its war aims. This uncertainty has affected financial markets, which have seen considerable volatility. Stock markets have seen widespread falls, with airline, travel and AI-heavy stocks being particularly vulnerable.
If the war is concluded relatively swiftly, the economic effects could be relatively small. If the war continues, and especially if the Gulf countries are drawn further into the conflict and if the conflict spreads to other countries, the economic effects could be much more substantial. A prolonged conflict could see oil prices remaining above $100 per barrel, potentially increasing global inflation by 1 percentage point or more. This would slow or halt the move by central banks to cut rates and thereby reduce global economic growth – potentially, as we have seen, leading to stagflation.
The uncertainty was reflected in the decision of the Fed to keep interest rates unchanged at its meeting on 17/18 March. The Fed has the twin targets of keeping inflation close to 2% and maximising employment. Fed Chair, Jay Powell, acknowledged the current tension between the two goals: ‘upward risks for inflation and downward risks for employment, and that puts us in a difficult situation’. He also recognised that the future for inflation and the economy was highly uncertain as the war developed. This made interest rate setting difficult.
Then there is the issue of a potential new international refugee crisis. If the economic and political system in Iran deteriorates rapidly, this could trigger a wave of migration to neighbouring countries, such as Turkey, already hosting large numbers of refugees. Many could seek sanctuary further afield in Europe, with several countries already facing a backlash against immigration. The political and economic effects of this on host countries could be significant – but as yet, highly uncertain.
Articles
- Assessing the global economic impact of the Middle East war
ING, Carsten Brzeski, Warren Patterson, James Knightley and Deepali Bhargava (5/3/26)
- How the Hormuz closure could affect food, medicines and smartphones
BBC News Verify, Ben Chu (27/3/26)
- How will the Iran war affect the global economy?
Chatham House, Neil Shearing (6/3/26)
- ‘The stakes are enormous’: how a prolonged Iran war could shock the global economy
The Guardian, Richard Partington (22/3/26)
- Iran war is latest threat to a global economy rattled by Trump
Aljazeera, John Power (7/3/26)
- Why an Iran war inflation shock could wreck global economic recovery
The Guardian, Phillip Inman and Kalyeena Makortoff (8/3/26)
- Why has the Iran war sparked fears of stagflation for the global economy?
The Guardian, Luca Ittimani (9/2/26)
- Why the price of oil matters more than you might think
BBC News, Natalie Sherman and Mitchell Labiak (10/3/26)
- Strait of Hormuz: Factsheet
IEA (February 2026)
- Could this energy crisis be worse for the global economy than COVID?
The Conversation, Adi Imsirovic (26/3/26)
- Faisal Islam: Oil price spiral may be slowed but not stopped by G7 emergency move
BBC News, Faisal Islam (9/3/26)
- What on earth is going on with the oil price?
BBC News, Jemma Crew (12/3/26)
- Asia scrambles to confront energy crisis unleashed by Iran war – with no end in sight
The Guardian, Callum Jones (12/3/26)
- The grim choice facing the Trump administration: Economic or naval collapse?
CNN, Phil Mattingly and Zachary Cohen (9/3/26)
- Israel strikes Iran’s South Pars gasfield hours after forces kill intelligence minister
The Guardian, Lorenzo Tondo and William Christou (18/3/26)
- What Fed Chair Jerome Powell said — and didn’t say — about the oil crisis
Yahoo Finance, Jake Conley (19/3/26)
- What strikes on the world’s largest natural gas sites could do to the global economy
CNN, Hanna Ziady (19/3/26)
- How the Iran Conflict May Fuel a New International Refugee Crisis
Forbes, Andy J Semotiuk (5/3/26)
- Iran’s neighbours brace for fallout as war threatens new refugee crisis
Aljazeera, Abid Hussain (17/3/26)
- Two months into the Iran war, almost everybody is a loser
CNN, Ivana Kottasová (2/5/26)
Data
Report
Questions
- Who are the biggest gainers and losers from disruption to oil supplies from the Persian Gulf?
- Illustrate the effect of the current oil price shock on an aggregate demand and supply diagram (either static or dynamic).
- Why is the Iranian war likely to be less damaging to the European economy than the Ukrainian war has been?
- Why have AI-related stock prices been vulnerable to the uncertainty caused by the Iranian war?
- How have the Bank of England and the Federal Reserve Bank responded to higher oil prices and the broader economic effects of the war? Why might their responses be different in the coming months?
- What is the likely impact of the Iranian war on global economic recovery?
- How might the Iranian war affect global economic alliances?
- How is the current oil price shock likely to affect the eurozone? Will it be different from the oil price shock that followed the Russian invasion of Ukraine?
- What are the likely economic effects of large-scale migration caused by the war?
Donald Trump is keen to lower US interest rates substantially and rapidly in order to provide a boost to the US economy. He is also keen to reduce the cost of living for US citizens and sees lower interest rates as a means of reducing the burden of debt servicing for both consumers and firms alike.
But interest rates are set by the US central bank, the Federal Reserve (the ‘Fed’), which is formally independent from government. This independence is seen as important for providing stability to the US economy and removing monetary policy from short-term political pressures to cut interest rates. Succumbing to political pressures would be likely to create uncertainty and damage long-term stability and growth.
Yet President Trump is pushing the Fed to lower interest rates rapidly and despite three cuts in a row of 0.25 percentage points in the last part of 2025 (see chart below), he thinks this as too little and is annoyed by suggestions that the Fed is unlikely to lower rates again for a while. He has put great pressure on Jerome Powell, the Fed Chair, to go further and faster and has threatened to replace him before his term expires in May this year. He has also made clear that he is likely to appoint someone more willing to cutting rates.
The Federal Reserve headquarters in Washington is currently being renovated. The nine-year project is costing $2.5 billion and is due to be completed next year. President Trump has declared that the project’s costs are excessive and unnecessary.
On 11 January, Federal prosecutors confirmed that they were opening a criminal investigation into Powell, accusing him of lying to Congress in his June 2025 testimony regarding the scope and costs of the renovations.
Powell responded by posting a video in which he claimed that the real reason that he was being threatened with criminal charges was not because of the renovations but because the Fed had ignored President Trump’s pressure and had set interest rates:
based on our best assessment of what will serve the public, rather than following the preferences of the President. This is about whether the Fed will be able to continue to set interest rates based on evidence and economic conditions – or whether, instead, monetary policy will be directed by political pressure or intimidation.
The Fed’s mandate
The Federal Reserve Board decides on monetary policy and then the Federal Open Market Committee (FOMC) decides how to carry it out. It decides on interest rates and asset sales or purchases. The FOMC meets eight times a year.
The Fed is independent of both the President and Congress, and its Chair is generally regarded as having great power in determining the country’s economic policy.
Since 1977, the Fed’s statutory mandate has been to promote the goals of stable prices and maximum employment. Because of the reference to both prices and employment, the mandate is commonly referred to as a ‘dual mandate’. Its inflation target is 2 per cent over the long run with ‘well anchored’ inflationary expectations.
The dual mandate is unlike that of the Bank of England, the European Central Bank, the Bank of Japan and most other central banks, which all have a single key mandate of achieving a target of a 2 per cent annual rate of consumer price inflation over a particular time period.
With a dual mandate, the two objectives may well conflict from time to time. Moreover, changes in monetary policy affect these objectives with a lag and potentially over different time horizons. Hence, an assessment may have to be made of which is the most pressing problem. This does give some leeway in setting interest rates somewhat lower than if there were a single inflation-rate target. Nevertheless, the assessment is in terms of how best to achieve the mandate and not to meet current political goals.
Statement by former Fed Chairs and Governors
On 12 January, three former Chairs of the Federal Reserve (Janet Yellen, Ben Bernanke and Alan Greenspan), four former Treasury Secretaries (Timothy Geithner, Jacob Lew, Henry Paulson and Robert Rubin) and seven other top former economic officials issued the following statement (see Substack link in the Articles section below):
The Federal Reserve’s independence and the public’s perception of that independence are critical for economic performance, including achieving the goals Congress has set for the Federal Reserve of stable prices, maximum employment, and moderate long-term interest rates. The reported criminal inquiry into Federal Reserve Chair Jay Powell is an unprecedented attempt to use prosecutorial attacks to undermine that independence. This is how monetary policy is made in emerging markets with weak institutions, with highly negative consequences for inflation and the functioning of their economies more broadly. It has no place in the United States whose greatest strength is the rule of law, which is at the foundation of our economic success.
Response of investors
What will happen to the dollar, US bond prices, share prices and US inflation, and what will happen to investment, depends on how people respond to the threat to the Fed’s independence. Initially, there was little response from markets, with investors probably concluding that President Trump is unlikely to be able to sway FOMC members. What is more, several Republican lawmakers have begun criticising the Trump administration’s criminal investigation, making it harder for the President to influence Fed decisions.
Even if Powell is replaced, either in the short term or in May, by a chair keen to pursue the Trump agenda, that chair will still be just one of twelve voting members of the FOMC.
Seven are appointed by the President, but serve for staggered 14-year terms. Four have been appointed by President Trump, but the other three were appointed by President Biden, although one – Lisa Cook – is being indicted by the Supreme Court for mortgage fraud, with the hearing scheduled for January 21. She claims that this is a trumped-up charge to provide grounds for removing her from the Fed. If she is removed, President Trump could appoint a replacement minded to cut rates.
The other five members include the President of the New York Fed and four of the eleven other regional Fed Presidents serving in rotation. These four are generally hawkish and would oppose early rate cuts.
Thus it is unlikely that President Trump will succeed in pushing the Fed to lower interest rates earlier than they would have done. For that reason, markets have remained relatively sanguine.
Nevertheless, Donald Trump’s actions could well cause investors to become more worried. Will he try to find other ways to undermine the Fed? Will his actions over Venezuela, Cuba, Greenland and Iran, let alone his policies towards Ukraine and Russia and towards Israel and Gaza, heighten global uncertainty? Will his actions towards Venezuela and his desire to take over Greenland embolden China to attempt to annex Taiwan, and Russia to continue to resist plans to end the war in Ukraine or to make stronger demands?
Such developments could cause investor confidence to wane and for stock markets to fall. Time will tell. I think we need a crystal ball!
Videos
Articles
- Federal prosecutors open criminal investigation into the Fed and Jerome Powell
CNN, Bryan Mena (11/1/26)
- The Fed just gave a rare look at its $2.5 billion renovation — right before Trump’s tour
CNN, Bryan Mena (24/7/25)
- ‘A bone-headed move’: Trump’s shocking battle with Powell could badly backfire
CNN, Matt Egan (12/1/26)
- Why Powell is fighting back against Trump: The US economy is at stake
CNN, Bryan Mena (13/1/26)
- Fed chair Powell hits out at ‘unprecedented’ probe by US justice department
BBC News, Ana Faguy and Osmond Chia (12/1/26)
- Justice department opens investigation into Jerome Powell as Trump ramps up campaign against Federal Reserve
The Guardian, Callum Jones (12/1/26)
- Some Republicans speak out against DoJ investigation into Fed chair
The Guardian, Joseph Gedeon (12/1/26)
- Trump’s attempts to influence Fed risk 1970s-style inflation and global backlash
The Guardian, Richard Partington (12/1/26)
- Statement on the Federal Reserve
Substack, 14 signatories (12/1/26)
- Yellen says Powell probe ‘extremely chilling’ for Fed independence, market should be concerned
CNBC, Jeff Cox (12/1/26)
- Global central bankers unite in defense of Fed Chair Jerome Powell
CNBC, Holly Ellyatt (13/1/26)
- Trump attacks Powell again amid Fed independence fears: ‘That jerk will be gone soon’
CNBC, Kevin Breuninger (13/1/26)
- Former Fed chairs condemn criminal investigation into Jerome Powell
BBC News, Danielle Kaye (12/1/26)
- Fed: Towards a very divided Fed in the coming months and quarters
CPR AM, Bastien Drut (28/11/25)
- Treasury Yields Diverge as Powell Probe Rekindles Fed Independence Risk
Investing.com, Khasay Hashimov (12/1/26)
- Instant View: Investors react as Trump-Fed feud escalates
Reuters (12/1/26)
- Fighting the Fed, Trump tries credit easing by decree
Reuters, Mike Dolan (13/1/26)
- Trump’s attacks on the Federal Reserve risk fuelling US inflation and ending dollar dominance
The Conversation, Emre Tarim (13/1/26)
Questions
- What are the arguments for central bank independence?
- What are the arguments for control of monetary policy by the central government?
- Assess the above arguments.
- Find out what has happened to interest rates, the US stock market and the dollar since this blog was written.
- How do the fiscal decisions by government affect monetary policy?
- Compare the benefits of the dual mandate system of the Fed with those of the single mandate of the Bank of England and ECB.
For a while now, debate has raged over how to revive the fortunes of the London Stock Exchange (LSE). Since the 2008 financial crisis, the market has suffered a lack of investment, poor liquidity and low performance. This has produced a moribund financial market which has become unattractive to both investors and companies. Returns from the UK market lag international competitors, particularly the USA (see the chart).

Investment in the S&P 500 Index over the period would have produced annualised rates of return of 14.35%, more than double that from the FTSE 100 Index. Part of this underperformance is due to the industrial mix of the listed companies: low-growth energy and mining compared to the high-growth technology sectors in the USA. This has led to the perception that London is not a place for firms to list, particularly those in high-growth sectors.
In 2024, 88 companies choose to delist or transfer their primary listing elsewhere. Only 18 took their place. Several big companies from a range of industries, including Ashtead, Flutter and CRH have transferred their primary listing to New York or have plans to do so.
The new Labour government views stimulating higher levels of investment though the London market as an important element in its drive to boost productivity and growth in the UK. Recently, it has been reported that investment institutions have been lobbying the UK government to reduce significantly the tax-free allowance for Cash Individual Savings Accounts (ISAs) as a way to encourage more of UK households’ savings to be channelled through the UK stock market.
Currently, UK savers can save up to £20 000 annually into ISAs without paying tax on the interest earned. This can be held solely in Cash ISAs, or in a combination of Cash plus Stocks and Shares ISAs. The tax-free instruments which were introduced by a Labour government in 1999 to encourage higher savings have proved immensely popular. Data from Paragon Bank indicate that over £350 billion are held in these accounts. However, under the new proposals, the amount which would be allowed to be saved as cash has been rumoured to be cut to £4000 per year, with the hope that some of it will be invested in the UK stock market.
The proposals have proved controversial, with high-profile figures voicing opposition. In this blog, we’ll analyse the reasons behind the proposal and discuss whether it will have the desired effect of stimulating higher levels of investment. We’ll also discuss other proposed policies for making the LSE a more effective channel for investment flows to boost economic growth.
Stock markets and the saving and investment channel
The main reason for the proposed ISA change is to encourage more investment in the UK stock market. By reducing the amount which can be saved in Cash ISAs, the government hopes to encourage savers to invest in Stocks and Shares ISAs instead, particularly ones linked to the UK market. This would increase the amount of finance capital in the market, thereby boosting its liquidity. This would then make it an attractive place for young, vibrant UK and foreign companies to list.
An active, liquid secondary market in shares is important to attract firms to list on stock exchanges by issuing shares to outside investors. Traditionally, this channel has been important to the growth and development of firms.
Existing savings in Cash ISAs are deposited with financial institutions such as banks and building societies. Through the credit-creation process such funds can be used to finance productive investment. In countries like the UK, lending by financial institutions is an important way that investment is financed, particularly for small and medium-sized enterprises. However, scale limits, regulatory restrictions and the need to diversify lending properly means that there are limits to the financing available for company investment through these institutions.
Capital markets like the LSE are intended to meet these larger-scale requirements. Financial claims, such as debt and equity, are divided into atomised instruments and sold to outside investors to fund investment and business growth.
Further, the desire for a capital injection to finance growth is not the only reason that firms seek stock market listings. Founders of companies may have a lot of wealth invested in the equity of their firms. Selling some of their equity to outside investors through a stock market listing is a way of diversifying their wealth. However, if they are to maximise the potential sale price, there must be an active, liquid secondary market to encourage investors to buy shares in the primary market.
Proponents of reform want to encourage a greater appetite for risk among UK investors, which will produce more savings being channelled through the LSE.
One issue is whether savers will respond in the way anticipated and channel more funds through the UK stock market. Many savers like the security of Cash ISAs. Such vehicles offer a low-risk/low-return combination, which savers like because the tax benefits boost returns. A survey by the Nottingham Building Society found that a substantial number of Cash ISA savers are concerned that the proposed changes could affect their ability to save for important financial goals, such as buying a house or building an emergency fund. Higher-risk Stocks and Shares ISAs are not suitable for such savings because of the potential to lose the initial amount invested. Many may not be prepared to do so and one-third suggested they would save less overall.
According to the survey, only 38% of Cash ISA holders said they would consider investing in Stocks and Shares ISAs if the Cash ISA allowance were reduced. It may be difficult to alter such risk-averse preferences given the average amount saved through ISAs and demographics. In 2022/23, the average amount subscribed to ISAs was £5000. This does not suggest that average households have a significant surplus of cash that they may want to investment at a high risk through the stock market. Indeed, many may want to have access to the cash at short notice and so are not prepared to forgo liquidity for the time needed to accrue the benefits of compounding which stock market investing produces.
Demographics may also play a role in this. Many of those who save more are now retired, or near retirement. They are less likely to see the appeal of compounding returns over long periods through investment in shares. Instead, with shorter investment horizons, they may only see the potential for losses associated with Stocks and Shares ISAs. Indeed, they will be starting to liquidate their long-term positions to draw income in retirement. Therefore, they may save less.
For others, who may be prepared to accept the additional risk, with the prospect of higher returns in the way that advocates of the reform hope for, the reduction in the Cash ISA allowance does not necessarily mean that they will invest in Stocks and Shares ISAs linked to the UK market. Since returns from the UK market have lagged international competitors, it may be that savers will channel their savings to those international markets, particularly in the USA, where the risk–return relationship has been more rewarding. Doing so has been made much easier and cheaper through a combination of economic forces including technological advances, regulatory changes and increased competition. This makes it much easier for UK savers to channel investment funds to wherever potential return is highest. At the moment, this is unlikely to be the UK, meaning that the anticipated boost to investment funds may not be as much as anticipated.
Critics of the proposal also question the motives of investment fund managers who have been lobbying government. They argue that the reforms will mean that many people who do now choose to save in Stocks and Shares ISAs will buy funds managed by fund managers who will receive fees for doing so. Critics argue that it is the prospect of higher fees which is the real motive behind the lobbying, not any desire to boost investment and growth.
What alternatives are available to boost the London Stock Exchange
The low valuations of LSE-listed companies compared to their international counterparts, particularly those in the USA, has discouraged growing firms from listing in London. To address this, there have been calls to enhance corporate governance standards and reduce regulatory burdens for listed companies.
This has already been recognised by the authorities. In 2024, UK regulators approved the biggest overhaul of rules regulating London-listed companies. The new listing rules will hand more power to company bosses to make decisions without shareholder votes. They will give companies more flexibility to adopt dual-class share structures used by founders and venture capital firms to give themselves stronger voting rights than other investors. This is particularly popular for founders who want to diversify their wealth without sacrificing control and is used frequently by tech companies and venture capitalists when listing in the USA. Such reforms may attract more companies in high-growth sectors to list in London.
Tax policies which provide the right incentives to buy and sell shares could also encourage more investment in the LSE. For instance, the repeal in the mid-1990s of the preferential tax treatment of dividend income for UK pension funds and insurance companies is seen as a major factor in discouraging those institutions from investing more funds in the London market. Since tax on capital gains is only liable when they are realised, this reduces their present value versus the equivalent amount on dividends.
As the following table illustrates, given the significantly higher percentage of total returns derived from dividends in the LSE compared to other exchanges, the equal tax treatment of dividend and capital gains provides an incentive to seek jurisdictions where capital gains predominate. This is what UK pension funds have done. Data from the Office of National Statistics show that in 2024, 77% of UK occupational pensions equity investments were overseas.

Reinstating this tax benefit could stimulate greater demand for UK equity from this significant sector, boosting liquidity in the London market. Allied to this are proposals from the UK government to consolidate the fragmented UK pension industry to achieve greater scale economies in that channel for investment. This can reduce financing costs, boosting the marginal return from UK investments for these funds, encouraging greater investment in the UK market (ceteris paribus).
Further, the 2.5% stamp duty on share purchases has been viewed as another disincentive for both retail and institutional investors to engage in security trading on the London Stock Exchange. The duty, which is much higher than in peer economies, effectively raises the expected rate of return on UK equites which depresses perceptions of their values and prices. Its removal may raise trading volumes, improving the liquidity of the market and be offset by increased tax revenues in the future. However, the Treasury suggests that the removal of stamp duty is doubtful, since it would create a significant hole in the UK government’s budget.
Ultimately, many of these reforms may have limited impact on investment. Efforts to boost confidence in the stock market will depend on improving the overall economic environment in the UK. Therefore, it will be the wider policies promoting growth in general which will increase the rates of return offered by London-listed firms and be more significant to attracting capital to London.
However, many of these are controversial themselves, such as relaxing laws around planning permissions and addressing business uncertainties around post-Brexit trading arrangements with the European Union. These broader economic measures could help make the UK generally, and the LSE specifically, more appealing to both domestic and international investors.
Conclusion
The UK government’s proposal to reduce the Cash ISA allowance is part of a broader strategy to boost investment in the stock market and stimulate economic growth. While this change could lead to more capital being directed towards productive investments, it also poses challenges for savers who like the security and simplicity of Cash ISAs.
The ultimate impact will depend on how savers respond to these changes. The potential reduction in overall savings rates could counteract some of the intended benefits. Further, the extent to which they are prepared to channel their savings into UK-listed companies will be important. If many seek higher returns elsewhere, the impact on the UK stock market may be limited. In any case, policies to address the problems of the UK stock market will only work if the wider issues associated with UK productivity and growth are addressed.
Articles
Data
Questions
- Explain how banks use cash ISAs to finance investment through credit creation.
- What do stock markets offer which may boost investment and economic growth?
- What are the issues with the London Stock Exchange which is making it unattractive for raising finance?
- How is the rumoured ISA reform intended to help address these issues?
- Analyse the extent to which it will do so.
- How might some of the broader reforms proposed by the UK government influence rate of return on UK equities and attract capital?
A common practice of international investors is to take part in the so-called ‘carry trade’. This involves taking advantage of nominal interest rate differences between countries. For example, assume that interest rates are low in Japan and high in the USA. It is thus profitable to borrow yen in Japan at the low interest rate, exchange it into US dollars and deposit the money at the higher interest rate available in the USA. If there is no change in the exchange rate between the dollar and the yen, the investor makes a profit equal to the difference in the interest rates.
Rather than depositing the money in a US bank account, an alternative is to purchase US bonds or other assets in the USA, where the return is again higher than that in Japan.
If, however, interest-rate differentials narrow, there is the possibility of the carry trade ‘unwinding’. Not only may the carry trade prove unprofitable (or less so), but investors may withdraw their deposits and pay back the loans. This, as we shall, can have adverse consequences on exchange rates.
The problem of an unwinding of the carry trade is not new. It worsened the underlying problems of the financial crisis in 2008. The question today is whether history is about to repeat itself with a new round of unwinding of the carry trade threatening economic growth and recovery around the world.
We start by looking at what happened in 2008.
The carry trade and the 2008 financial crisis
Prior to the financial crisis of 2008, current account deficit countries, such as the UK, USA and Australia, typically had relatively high interest rates, while current account surplus countries such as Japan and Switzerland had relatively low ones. Figure 1 shows central bank interest rates from 2005 to the current day (click here for a PowerPoint).
The carry trade saw investors borrowing money in Japan and Switzerland, exchanging it on the foreign exchange market, with the currency then deposited in the UK, USA and Australia. Hundreds of billions worth of dollars were involved in this carry trade.
If, however, the higher interest rates in the UK and other deficit countries were simply to compensate investors for the risk of currency depreciation, then there would be no excessive inflow of finance. The benefit of the higher interest rate would be offset by a depreciating currency. But the carry trade had the effect of making deficit currencies appreciate, thereby further boosting the carry trade by speculation of further exchange rate rises.
Thus the currencies of deficit countries appreciated, making their goods less competitive and worsening their current account deficit. Between 1996 and 2006, the average current account deficits as a percentage of GDP for Australia, the USA and the UK were close to 4½, 4 and 2, respectively. Between January 1996 and December 2006, the broad-based real exchange rate index of the Australian dollar appreciated by 17%, of the US dollar by 4% and of sterling by some 23%.
Currencies of surplus countries depreciated, making their goods more competitive and further boosting their current account surpluses. For example, between 2004 and 2006 the average current account surpluses as a percentage of GDP for Japan and Switzerland were 3½ and 13, respectively. Their short-term interest rates averaged a mere 0.1% and 1.0% respectively (compared with 3.4%, 4.7% and 5.7% for the USA, the UK and Australia). Yet between January 2004 and December 2006, the real exchange rate index of the yen depreciated by 21%, while that of the Swiss franc depreciated by 6%.
With the credit crunch of 2007/8, the carry trade unwound. Much of the money deposited in the USA had been in highly risky assets, such as sub-prime mortgages. Investors scrambled to sell their assets in the USA, UK and the EU. Loans from Japan and Switzerland were repaid and these countries, seen as ‘safe havens’, attracted deposits. The currencies of deficit countries, such as the UK and USA, began to depreciate and those of surplus countries, such as Japan and Switzerland, began to appreciate. Between September 2007 and September 2008, the real exchange rate indices of the US dollar and sterling depreciated by 2% and 13% respectively; the yen and the Swiss franc appreciated by 3% and 2¾%.
This represented a ‘double whammy’ for Japanese exporters. Not only did its currency appreciate, making its exports more expensive in dollars, euros, pounds, etc., but the global recession saw consumers around the world buying less. As a result, the Japanese economy suffered the worst recession of the G7 economies.
The carry trade in recent months
Since 2016, there has been a re-emergence of the carry trade as the Fed began raising interest rates while the Bank of Japan kept rates at the ultra low level of –0.1% (see Figure 1). The process slowed down when the USA lowered interest rates in 2020 in response to the pandemic and fears of recession. But when the USA, the EU and the UK began raising rates at the beginning of 2022 in response to global inflationary pressures, while Japan kept its main rate at –0.1%, so the carry trade resumed in earnest. Cross-border loans originating in Japan (not all of it from the carry trade) had risen to ¥157tn ($1tn) by March 2024 – a rise of 21% from 2021.
The process boosted US stock markets and contributed to the dollar appreciating against the yen (see Figure 2: click here for a PowerPoint).
Although this depreciation of the yen helped Japanese exports, it also led to rising prices. Japanese inflation rose steadily throughout 2022. In the 12 months to January 2022 the inflation rate was 0.5% (having been negative from October 2020 to August 2021). By January 2023, the annual rate had risen to 4.3% – a rate not seen since 1981. The Bank of Japan was cautious about raising interest rates to suppress this inflation, however, for fear of damaging growth and causing the exchange rate to appreciate and thereby damaging exports. Indeed, quarterly economic growth fell from 1.3% in 2023 Q1 to –1.0% in 2023 Q3.
But then, with growth rebounding and the yen depreciating further, in March 2024 the Bank of Japan decided to raise its key rate from –0.1% to 0.1%. This initially had the effect of stabilising the exchange rate. But then with the yen depreciating further and inflation rising from 2.5% to 2.8% in May and staying at this level in June, the Bank of Japan increased the key rate again at the end of July – this time to 0.25% – and there were expectations that there would be another rise before the end of the year.
At the same time, there were expectations that the Fed would soon lower its main rate (the Federal Funds Rate) from its level of 5.33%. The ECB and the Bank of England had already begun lowering their main rates in response to lower inflation. The carry trade rapidly unwound. Investors sold US, EU and UK assets and began repaying yen loans.
The result was a rapid appreciation of the yen as Figure 3 shows (click here for a PowerPoint). Between 31 July (the date the Bank of Japan raised interest rates the second time) and 5 August, the dollar depreciated against the yen from ¥150.4 to ¥142.7. In other words, the value of 100 yen appreciated from $0.66 to $0.70 – an appreciation of the yen of 6.1%.
Fears about the unwinding of the carry trade led to falls in stock markets around the world. Not only were investors selling shares to pay back the loans, but fears of the continuing process put further downward pressure on shares. From 31 July to 5 August, the US S&P 500 fell by 6.1% and the tech-heavy Nasdaq by 8.0%.
As far as the Tokyo stock market was concerned, the appreciation of the yen sparked fears that the large Japanese export sector would be damaged. Investors rushed to sell shares. Between 31 July and 5 August, the Nikkei 225 (the main Japanese stock market index) fell by 19.5% – its biggest short-term fall ever (see Figure 4: click here for a PowerPoint).
Although the yen has since depreciated slightly (a rise in the yen/dollar rate) and stock markets have recovered somewhat, expectations of many investors are that the unwinding of the yen carry trade has some way to go. This could result in a further appreciation of the yen from current levels of around ¥100 = $0.67 to around $0.86 in a couple of years’ time.
There are also fears about the carry trade in the Chinese currency, the yuan. Some $500 billion of foreign currency holdings have been acquired with yuan since 2022. As with the Japanese carry trade, this has been encouraged by low Chinese interest rates and a depreciating yuan. Not only are Chinese companies investing abroad, but foreign companies operating in China have been using their yuan earnings from their Chinese operations to invest abroad rather than in China. The Chinese carry trade, however, has been restricted by the limited convertibility of the yuan. If the Chinese carry trade begins to unwind when the Chinese economy begins to recover and interest rates begin to rise, the effect will probably be more limited than with the yen.
Articles
- A popular trading strategy just blew up in investors’ faces
CNN, Allison Morrow (7/8/24)
- The big ‘carry trade’ unwind is far from over, strategists warn
CNBC, Sam Meredith (13/8/24)
- Unwinding of yen ‘carry trade’ still threatens markets, say analysts
Financial Times, Leo Lewis and David Keohane (7/8/24)
- The yen carry trade sell-off marks a step change in the business cycle
Financial Times, John Plender (10/8/24)
- Forbes Money Markets Global Markets React To The Japanese Yen Carry Trade Unwind
Forbes, Frank Holmes (12/8/24)
- 7 unwinding carry trades that crashed the markets
Alt21 (26/1/23)
- A carry crash also kicked off the global financial crisis 17 years ago — here’s why it’s unlikely to get as bad this time
The Conversation, Charles Read (9/8/24)
- What is the Chinese yuan carry trade and how is it different from the yen’s?
Reuters, Winni Zhou and Summer Zhen (13/8/24)
- Carry Trade That Blew Up Markets Is Attracting Hedge Funds Again
Yahoo Finance/Bloomberg, David Finnerty and Ruth Carson (16/8/24)
- Currency Carry Trades 101
Investopedia, Kathy Lien (9/8/24)
- Carry Trades Torpedoed The Market. They’re Still Everywhere.
Finimize, Stéphane Renevier (13/8/24)
Questions
- What factors drive the currency carry trade?
- Is the carry trade a form of arbitrage?
- Find out and explain what has happened to the Japanese yen since this blog was written.
- Find out and explain some other examples of carry trades.
- Why are expectations so important in determining the extent and timing of the unwinding of carry trades?