NOMISMA

market rate

相場 / market-rate — Measuring

The price actually being paid in the market.

1 Rupee of Hyderabad 1 Rupee of HyderabadAH 1335 (circa 1917)
A photograph of what this word names.

Even if the system sets a ratio of 'one to fifteen,' if the market trades at 'one to sixteen,' the market is the correct one. Do not take the par value found in historical sources as the actual market rate of that era.