The Plaza Accord itself did not set a specific yen–dollar rate in September 1985; it was an agreement to devalue the dollar and let the yen appreciate , with market forces determining “how much.” But we can describe what the yen–dollar rate was around that time and how it moved after the accord.

Exchange rate at the time of the Plaza Accord (September 1985)

  • The Plaza Accord was signed on 22 September 1985 at the Plaza Hotel in New York.
  • In the weeks before that, the USD/JPY rate was roughly in the 230–250 yen per dollar range. Many sources cite about 240 yen per dollar as the prevailing level in mid‑September 1985.
  • That means the price of 1 dollar was roughly 240 yen , or equivalently, 1 yen ≈ 0.0042 dollars.

So if you’re asking “how much yen per dollar” under/around the Plaza Accord in September 1985, the answer is something like:

About 240 yen for 1 dollar (roughly 0.0042 dollars per yen).

What the Plaza Accord actually changed

The accord did not say “the yen will be X yen per dollar.” Instead:

  • The G‑5 (US, Japan, Germany, France, UK) agreed that “some further orderly appreciation of the main non‑dollar currencies is desirable.”
  • After the announcement, the dollar began a sharp decline:
    • The next Monday, the dollar fell about 4%.
* Over the next **two years** , the dollar fell roughly **40%** overall against major currencies, including the yen.
  • By early 1988, the yen had appreciated to around 120–130 yen per dollar , roughly half its September 1985 level.

Why there’s no single “Plaza Accord yen–dollar number”

Key points:

  • The Plaza Accord was a policy coordination agreement , not a fixed exchange-rate treaty.
  • It signaled that central banks would intervene to push the dollar down and the yen up, but the actual rate was determined by the market.
  • So in September 1985, the “yen–dollar” level under the Plaza Accord is simply the market rate at that time , not a fixed number baked into the text.

Quick numeric summary (September 1985)

  • Approximate USD/JPY rate : ~240 yen per dollar
  • Yen price in dollars : ~0.0042 USD per yen
  • After the accord : yen strengthened over the next couple of years, reaching roughly 120–130 yen/dollar by 1988.

Information gathered from public forums or data available on the internet and portrayed here.