USD/JPY pushed to a fresh 40-year high of ¥163.90 early Friday, and rising inflation in Japan isn't doing anything to stop the yen's slide.

Key Fact: USD/JPY hit ¥163.90 early Friday, marking another 40-year high against the yen.

Japan Inflation Rises, But the Yen Still Falls

Japan's latest inflation report gave traders another reason to keep selling the currency. Core inflation, which excludes fresh food prices, rose to 1.6% in June, matching forecasts and marking the first acceleration since March. Headline inflation climbed to 1.7%, while the "core-core" measure — which excludes both food and energy — eased slightly to 1.7%.

Normally, rising inflation supports a currency. Not this time. Traders remain focused on Japan's ultra-low interest rates, which continue to make the yen one of the world's favorite funding currencies for carry trades.

Oil Prices Add to the Pressure

Higher oil prices are compounding Japan's problems. Producer prices jumped 7.1% in June, the fastest pace since March 2023, even with government subsidies softening the blow for households. Because Japan imports most of its energy, a weaker yen makes every barrel more expensive — feeding imported inflation and squeezing corporate margins further.

Key Stat: Japan's producer prices rose 7.1% in June — the fastest pace since March 2023.

Can the Bank of Japan Change the Trend?

Currency intervention can slow a slide, but analysts note it rarely reverses the underlying trend without a broader policy shift. Reports this week suggest some Bank of Japan officials are growing concerned that a weak yen combined with rising fuel costs could keep inflation elevated for longer, potentially opening the door to faster rate hikes than markets currently expect.

Higher interest rates typically strengthen a currency by making local assets more attractive. But Japan has spent decades fighting weak inflation, and tightening policy too aggressively carries its own risks. Until the BOJ convinces markets it's ready to meaningfully narrow the rate gap with the US, traders may keep treating every yen rally as a selling opportunity.

Why It Matters

USD/JPY's 40-year high reflects a deeper structural tension in Japan's economy: inflation is rising, but not for reasons that make raising rates an easy call. For currency and macro-focused traders, USD/JPY has become one of the clearest live examples of how policy divergence between central banks can drive persistent, multi-year currency trends.

This article is for informational purposes only and does not constitute financial advice. Do your own research.