CPI stands for "Consumer Price Index." It is a measure of the average change over time in the prices of goods and services that households in a country purchase for consumption. The CPI is often used as a gauge of inflation, as increases in the index indicate that prices for consumer goods and services are generally rising.

CPI (Consumer Price Index) is calculated by measuring the price changes of a basket of goods and services that are commonly consumed by households. The prices of these items are collected regularly, and then compared to a base period. The percentage change in prices from the base period to the current period is the inflation rate, which is used to calculate the CPI. The formula for CPI is:

CPI = (Cost of basket in current period / Cost of basket in base period) x 100

The CPI provides an estimate of the average change in prices that consumers are paying for goods and services, and is used as a measure of inflation.