How is a dollar-based stock price calculated?
The calculation is a single division, but getting it right depends on matching each close to the correct day's exchange rate.
The formula
A dollar-based price is the lira closing price divided by the same day's USDTRY rate. A stock closing at 120 lira on a day when the rate is 40.00 is $3.00. Repeat that for every trading day and you have a dollar-based price series.
Which rate, which close
Every lira close must be matched with its own day's rate. Dividing today's price by yesterday's rate produces misleading jumps whenever the currency is volatile. On days the exchange is shut, neither price nor rate updates, so those days drop out of the series.
Dividends and splits
Return calculations need the adjusted close. When a stock splits, the raw price halves overnight — that is not a loss. An adjusted series removes those effects so the dollar return reflects real performance.
The same calculation on the index
At the 27 Oct 2026 close the BIST 100 stood at 11,151 points. Divided by that day's rate, it works out to $224.00. HisseUSD repeats this for every trading day back to 16 Sep 2016.
The figures in this section come from live data.
BIST 100 index chart in dollarsWhich exchange rate should be used?
The USDTRY rate from the same day as the closing price. Mixing prices and rates from different days corrupts the series.
How is a dollar-based return calculated?
Divide the dollar price at the end of the period by the dollar price at the start, subtract 1, then multiply by 100 for a percentage.
The example figures in these guides update automatically with the end-of-day close. Not investment advice.