The World Bank has used the Atlas method since 1993 to estimate the economic size of countries based on their gross national income (GNI) in U.S. dollars.
To convert a country's GNI from its local currency to U.S. dollars, the Atlas method uses a conversion factor that averages exchange rates over three years. This helps reduce the impact of temporary exchange rate changes. Additionally, it adjusts for differences in inflation rates between the country (using its GDP deflator) and several developed countries (using a weighted average of their GDP deflators in Special Drawing Rights, or SDR, terms). The converted GNI in U.S. dollars is then divided by the country's midyear population to determine GNI per capita.
