Gross domestic product (GDP) is a monetary measure of the value of all final goods and services produced in a defined period (quarterly or yearly).
Nominal GDP estimates are commonly used to determine the economic performance of a whole country or region, and to make international comparisons. Nominal GDP, however, does not reflect differences in the cost of living and the inflation rates of the countries; therefore using a GDP PPP per capita basis is arguably more useful when comparing differences in living standards between nations.