01What a high or low reading means
When the rate climbs, the yen is weakening against the dollar, which makes Japanese exports cheaper for foreign buyers and erodes the purchasing power of yen-held savings. When the rate falls, the yen is strengthening. Sustained yen strength in the 1990s and 2010s came alongside Japanese deflation pressure and exporters losing competitiveness. Each 10-yen move is large by historical standards and tends to draw policy attention.
02Why yen per dollar rather than dollar per yen
The market convention for USD/JPY quotes the yen per dollar (higher number = weaker yen), the opposite direction from most currency pairs. Sticking with the convention makes the chart directly comparable to dealer screens and news headlines, even though it can feel inverted for readers used to dollar-per-foreign-currency quoting.
03Limitations
This is the bilateral nominal rate against a single counterparty (the US dollar), so it captures neither yen moves against other currencies nor relative inflation between Japan and its trading partners. It also excludes the carry-trade and hedging flows that move the actual cross in real time. Treat the chart as context for the yen's value versus the dollar specifically, not investment advice.
04How to read the reference lines
Three overlays are computed from the full series and do not move when you change the range selector. The shaded band marks the full historical range from the 2011 strong-yen low near 77 to the 1986 weak-yen high near 163. The median line sits near 114, the middle of all monthly readings since 1986. The previous-max line marks the highest reading before the most recent 12 months, which is still the 1986 Plaza Accord aftermath peak near 163, meaning the recent yen weakness has approached but not breached the all-time weak reading.