This document discusses nominal and real gross national product (GNP). Nominal GNP measures total output at current prices, while real GNP adjusts for inflation by using constant prices from a base year. To calculate real GNP, nominal GNP is divided by the GNP deflator, which is a price index that shows inflation. Comparing nominal and real GNP allows economists to distinguish between changes in output versus changes due to price inflation. Real GNP provides a more accurate view of economic growth by filtering out the effects of rising prices.