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
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)
Reproducible Calculation Steps
- Choose either the BIST 100 price index or a total-return index and do not mix them.
- Use the nearest common trading dates for the start and end.
- Calculate the nominal TRY result.
- Convert every cash flow with that date's USD/TRY rate to calculate a separate USD result.
- 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.
Read the calculation in an auditable way
The numbers in this article are not intended to turn a past price path into a certain forecast. Their purpose is to make the arithmetic reproducible when asset, dates, currency and contribution rule are explicit. First check what was actually bought: a price index, a total-return index with reinvested dividends, and a fund's net asset value do not measure the same thing. Bitcoin trades continuously, while equities, gold and indices follow trading sessions and closing times. A calendar date therefore may not provide the same kind of valid observation for every asset.
In a lump-sum scenario, the amount is divided by the historical price and the resulting units are valued at the end price. For recurring contributions, this is repeated at every contribution date; total invested is the sum of all valid purchases. Converting historical cash flows at today's price or FX rate creates units that could not have been bought then. The rule used for weekends, holidays or missing observations should therefore be visible alongside the result.
Costs, risk and limits
HowMuch? uses gross historical references. In a real account, spread, commission, tax, custody, fund charges and conversion costs can reduce the outcome. Fixed fees can matter more for small, frequent purchases, and a fund series may already incorporate an expense or dividend treatment that must not be double-counted. The best endpoint also does not mean the journey was easy: the same period may contain a severe drawdown whose recovery comes after the goal date. Near-term money, emergency reserves and personal capacity for loss must be considered separately from the scenario.
Next step
First reproduce this article's assumptions unchanged. Then change one variable only: move the start date by a year, change frequency, or view the result in the currency in which you spend. Record total contributions, end date and data cutoff for every run. This turns the calculator into a transparent test of which assumptions drive a result, rather than a tool that claims to give a certain answer.
A decision-before-action review framework
Once a comparison is complete, the first question should not be “which row made the most money?” First verify that the choice you would actually make matches the choice being compared. An equity price can be split-adjusted, while a real ETF has its own expenses and dividend treatment. A country index can rise in nominal points while local purchasing power or foreign-currency value moves differently. For crypto, custody method, counterparty risk and trading cost matter; for an index, fund tracking difference and tax treatment can produce a separate outcome. A historical table should not hide those distinctions. It should make clear which distinctions remain outside the calculation.
In a stronger experiment, keep the budget fixed and change only one variable. Moving the start date includes a different market cycle; changing contribution frequency changes purchase dates; changing currency exposes the FX effect. Changing several assumptions at once makes the reason for a different result impossible to identify. Recording ticker, data provider, date range, total contributions and market-day rule for every run makes later comparisons auditable.
The result must also fit the goal. Money needed soon for a deposit, education payment or business capital cannot necessarily absorb the same volatility as money for a flexible long-term objective. A profitable historical example does not tell an investor at what loss they would be forced to sell. Risk tolerance is emotional resilience, while risk capacity is the financial ability to continue without derailing the goal. Both constraints should sit above the historical result presented in this article.
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.
