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Regular Investing in BIST 100: How to Read 10 Years of Data

How to compare BIST 100 consistently in TRY and USD while accounting for index scale, FX, inflation and dividends.

Published: February 3, 2025Updated: August 3, 20263 min read
Regular Investing in BIST 100: How to Read 10 Years of Data
Measure
Price index
Period end
Dec 31, 2024
Prepared by: HowMuch? Editorial & Data Team
Data cutoff: December 31, 2024
Figures and links re-reviewed on August 3, 2026.
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BIST 100's Confusing Numbers

Raw BIST 100 index levels cannot be compared naively across a long period. Display-scale changes, the exact start date and the difference between a price index and a total-return index can materially change the result.

Treat this as a historical price-index example ending on December 31, 2024. Reproduce the live result in the calculator with the same dates and currency.

How Currency Erases Your Gains

AssetBIST 100 price index
Comparison period2015 – Dec 31, 2024
TRY resultNominal return
USD resultConverted with historical USD/TRY

A nominal rise in lira does not imply an equal increase in purchasing power. A sound comparison uses historical FX for the same dates, inflation and—where available—a total-return index that includes dividends.

Does This Make BIST a Bad Investment?

Whether BIST 100 beat inflation in a particular window must be tested with real returns calculated over identical start and end dates. Concentrating in one country and currency also adds country, FX and sector risk.

  • Measure FX risk separately: Compare TRY and USD outcomes over identical start and end dates
  • Track real returns: Our calculator's inflation-adjustment feature is built exactly for this
  • Sector matters: Banking, energy, and tech sectors move very differently from each other

1,000 TRY/Month DCA Simulation (5 Years)

PeriodJan 2020 – Dec 2024
Total invested60,000 TRY
Period-end valueReproduce in the live calculator

Reproducible Calculation Steps

  1. Choose either the BIST 100 price index or a total-return index and do not mix them.
  2. Use the nearest common trading dates for the start and end.
  3. Calculate the nominal TRY result.
  4. Convert every cash flow with that date's USD/TRY rate to calculate a separate USD result.
  5. Show CPI-adjusted purchasing power as a separate real-return result.

Historical display-scale changes can make raw index points misleading. Use an adjusted series and identify the exact ticker and provider.

What Is Excluded

A price index excludes dividends. With a real fund or equity portfolio, withholding tax, commissions, fund expenses, reinvestment timing and FX spread can change the result. TRY nominal, USD and real return should therefore be shown as three distinct measurements.

How Should You Use the Result?

This analysis is designed to make assumptions visible and reproducible, not to declare one universal winner. Change the amount, start date, currency and contribution frequency in the calculator to see how sensitive the outcome is. Review the worst window as carefully as the best one before making a decision.

A real investment can differ because of execution price, bid-ask spread, commission, tax, product expenses and the data provider's closing-time convention. The figures are therefore a gross historical comparison, not a personal return or a forecast.

Sources and methodology

This content is for informational purposes only. It does not constitute investment advice. Past performance does not guarantee future results.

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