Method to calculate Inflation
1. Collect price data on a typical 'shopping basket' of items from month to month
2. The CPI market basket is developed from detailed expenditure information
3. The content of the basket is fixed for a period of 12 months and different weights are attached to various items
4. The content and the weightings are reviewed regularly
5. To calculate changes in price, the government agency sets a base year for the total cost of the shopping basket, which is then converted into an index of 100
6. On a monthly basis, prices are collected again and the cost of the basket is recalculated resulting in a revised index number