Modular programming is a software design technique that emphasizes separating the functionality of a program into independent, interchangeable modules, such that each contains everything necessary to execute only one aspect of the desired functionality.
So if the value of the price index for the current year is equal to 165, and last year's value was 150, the rate would be calculated as: Inflation rate = (165 - 150) X100= 10.
The price index on its own does not give the inflation rate but it can be used to calculate the inflation rate. Let's use the Consumer Price Index as an example as is the most often used index to calculate the inflation rate.