The U.S. Treasury announced it will at least double the upper limit of its buyback operations for government debt with maturities of 10 years or more, aiming to boost market liquidity and proactively manage supply and demand in the U.S. bond market [1]. This policy shift led to a decline in U.S. Treasury yields as investors anticipated increased demand for longer-term government debt. Simultaneously, the yen strengthened against the dollar, reflecting expectations that the expanded buyback program would support bond prices and curb yields, thereby reducing the dollar's appeal [1].
In parallel, Japan's recent historic intervention to prop up the yen has had significant effects on global markets. Japanese investors net bought more than 5 trillion yen of foreign equities and long-term bonds over the two weeks ended August 15, compared to net selling of over 300 billion yen in the prior two weeks, according to Ministry of Finance data [2]. Market watchers noted that the yen's sharp rally following last month's joint U.S.-Japan currency intervention provided an opportunity for investors to acquire overseas assets at more favorable exchange rates [2].
Despite the intervention, the yen's gains were short-lived, strengthening from around 164 per dollar before the intervention to roughly 155, but then weakening back toward 159 against the greenback [2]. The U.S.-Japan 10-year yield spread stood at roughly 1.8 percentage points as of Thursday [2]. Analysts such as Jesper Koll of Monex Group and Masahiko Loo of State Street Global Advisors highlighted that the intervention 'turbo charged' the carry trade, with Japanese investors continuing to sell yen and buy higher-yielding foreign assets, particularly U.S. bills and bonds [2].
Market participants are closely monitoring the impact of the U.S. Treasury's expanded buybacks on both fixed income and currency markets, as well as the ongoing dynamics of the yen carry trade. Analysts suggest that unless the Bank of Japan raises rates enough to materially narrow the bond yield gap with the U.S., the yen will likely remain under pressure, and the incentives for carry trades will persist [2].
CONCLUSION
The U.S. Treasury's decision to expand long-dated bond buybacks has immediately impacted yields and currency markets, while Japan's intervention to support the yen has reinforced the attractiveness of the carry trade for investors. Both developments underscore the ongoing influence of interest rate differentials and central bank actions on global capital flows and market sentiment.