To calculate inflation, using the consumer price index that describes the average level of prices for goods and services in the economy. With this as a basis for determining the value of a so-called market basket – average set of goods and services required to meet the essential needs of one person. In accordance with the law of 31 March 2006 N44-FZ "On consumer basket as a whole," the composition of the basket is defined by three aggregated groups of commodities and services:
• Food
• Household goods (clothes, shoes, linen, household goods, etc.)
• Services (payment of utilities, transportation services, etc.).
The consumer price index is relative. To calculate inflation, determine the base year is the period of time in relation to which the estimated change in the price of the same goods and services. To do this, divide the sum of the products of the prices of the current year and output in the base year for the sum of the product of prices and output in the base year. The obtained value is expressed in percent.
The task in statistics is often required to calculate inflation for several years. It is known as increased prices for each year separately. For example, you need to calculate inflation for 2 years, if you know that for the first year prices rose by 20%, and for the second 25%. If you take the starting price level for X, the result of the first of the year inflation will be 1.2 X, and at the end of the second year – 1.2 X ? 1,25 = 1,5 H. Thus, inflation in 2 years is 50%.