deflátor

A deflátor, in economics, is a price index used to convert nominal values into real values by removing the effect of price changes. It measures how much prices have changed since a chosen base period and allows comparisons of quantities over time in real terms.

The deflator is typically calculated as: Deflator = (Nominal value / Real value) × 100. If a nominal statistic equals its real value in the base year, the deflator is 100. An increase in the deflator indicates that prices have risen since the base year.

Several deflators are commonly used. The GDP deflator is the broadest, reflecting price changes for all final goods and services produced domestically. It is the ratio of nominal GDP to real GDP and is published by national statistical agencies. Other important deflators include the consumer price index (CPI) deflator, which tracks changes in consumer prices, and the personal consumption expenditures (PCE) price deflator, used in some economies to measure inflation in household spending. Chain-weighted and fixed-base variants exist for different deflators.

Applications of deflators include converting nominal macroeconomic aggregates to real terms, calculating real growth rates, and isolating the impact of price changes from physical quantity changes. They are essential for comparing economic performance across periods and for monetary and fiscal analysis.

Limitations include that different deflators can move differently due to scope and methodology, which can affect real value estimates. The choice of base year and the treatment of new goods and quality changes can also influence results.

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