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Save in dollars or local currency?

Real local return is (1 + interest) / (1 + inflation) minus 1. Real return in dollar terms also divides by (1 + expected depreciation against the US dollar). When the currency is GHS, the interest field starts from the live 91-day Bank of Ghana T-bill rate.

Dollar terms-9.06%

Real return in local currency

-1.79%

After the inflation you entered. Before tax and fees.

Real return in dollar terms

-9.06%

After local inflation and the currency move against the dollar. US inflation is not subtracted.

Track on iOSTrack on AndroidSee Pro forecasts

How this is calculated

Assumptions

  • Real local return = (1 + interest) / (1 + inflation) - 1.
  • Real return in dollar terms = (1 + interest) / ((1 + inflation) x (1 + depreciation against USD)) - 1.
  • Depreciation is your guess, not a live exchange rate. If that guess already includes the inflation gap versus the United States, the dollar result counts that gap twice.
  • This ignores tax, fees, and the chance the rate changes before the year is over.
  • When the currency is GHS and you have not typed a rate, interest starts from the latest 91-day Bank of Ghana interest rate.

Worked example, not today's rate

Interest 15%, inflation 12%, depreciation 8%. Real local return is (1.15 / 1.12) - 1 = 2.68%. Real return in dollar terms is (1.15 / (1.12 x 1.08)) - 1 = -4.93%. The deposit beat local prices and still lost purchasing power in dollars.

Sources

  • The formula is the standard real-return identity. It is not a Bank of Ghana forecast.
  • GHS prefill uses the interest rate on the Ghana Treasury bill rates page, which cites the Bank of Ghana.

Educational software only. This is not financial, tax, or investment advice. Markets, inflation, fees, and your spending can all miss the model.

Last reviewed October 20, 2026 by Francis Eshun, Founder of Iron Wealth. He built the on-device tracker these pages describe. Iron Labs.

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