Yen tumbles to 4-decade low. Here are 3 reasons behind the historic slump

The Japanese yen fell to 162.23 against the US dollar, its weakest level since 1986, driven by dollar strength, rising expectations of US Federal Reserve rate hikes, and increased bearish positions worth $11.3 billion. The dollar index traded at 101.32, on track for a 1.4 percent quarterly gain after rising 1.6 percent in the opening quarter of 2026. Japanese Finance Minister Satsuki Katayama signalled readiness to intervene, with markets watching for potential action to support the currency amid speculation of further yen weakness.