Dollar falls 2.7% against the yen to 159, off a 40-year low, amid speculation of Japanese Ministry of Finance intervention

The dollar fell 2.7 percent against the yen on Thursday, 30 July 2026 (8 Mordad 1405), to 158.96 yen. In the previous session the yen had weakened as far as 164 per dollar, its lowest in 40 years. Sahmino's own price board recorded the same rate at 159.06, down 2.82 percent, at 21:29 Tehran time, confirming the direction and scale of the move from two independent readings.

According to Trading Economics, the rebound came amid speculation of intervention in the currency market by Japan's Ministry of Finance, which had sold the equivalent of $74.2 billion in the month to 27 May 2026. The yen's earlier weakness has been attributed to three factors: higher energy prices, concern over the fiscal deficit, and the interest rate gap with the United States. Surging LNG and petrol prices following the Iran war had raised dollar demand from Japanese energy importers.

The Bank of Japan decides on interest rates on Friday, 31 July 2026 (9 Mordad 1405), and is expected to leave the rate unchanged after its June increase. Japan's short-term policy rate rose from 0.75 percent to 1 percent in June 2026.