The Japanese yen extended its rapid rally on September 8, briefly gaining about 1% and rising to ¥152.89 per US dollar, bringing quotes close to the year‑high area around ¥152.1. Bloomberg notes that the cumulative 4% gain so far this month indicates the yen has moved into an organic uptrend. While the initial reversal was aided by the first coordinated intervention by Japanese and US authorities in 15 years, the current upside is unfolding without direct regulator action. As a result, the yen has posted the strongest performance among major world currencies in September, shedding its status as a market underperformer.
The broad advance confirms sustained investor interest in the Japanese currency. The yen has strengthened not only against the US dollar but also versus the euro, the British pound, and the Australian dollar, signaling a rise in its own intrinsic strength rather than a localized weakness in the dollar. The turnaround was swift. Last week, the US dollar traded as high as ¥160.39, by September 7, quotes had fallen almost to ¥154 with further weakening of the US currency.
Key drivers of the sharp change in market sentiment include growing expectations of imminent Bank of Japan rate hikes and circulating rumors of a possible reallocation of assets at the Government Pension Investment Fund (GPIF) in favor of domestic markets. The Ministry of Health, Labor, and Welfare, which oversees the pension fund, said any change to portfolio allocation parameters remains under review, but speculation on the subject has continued to provide strong support for the yen.