# Consumer Price Index (CPI) - Invert the procedure to compute real [[gdp|GDP]] and now quantities instead of prices! A more direct way to measure [[inflation]]. - Differences between CPI and [[gdp|GDP deflator]] - Kinds of goods included (bought by consumers vs produced domestically) - Weights - CPI and PPI are done by Bureau of Labor Statistics, GDP is done by Bureau of Economic Analysis - CPI-inflation is typically more volatile than GDP-deflator-inflation, e.g. oil, which is often imported, and not included in GDP - Two variants - Headline inflation: all goods and services included - Core inflation: food and energy excluded, which tend to be highly volatile