How the Consumer Price Index Is Calculated 4. Choose a Base year and Compute the Index(选择基年,计算价格指数): Designate one year as the base year Compute the index by dividing the price of the basket in one year the price in the base year and y multiplying by 100How the Consumer Price Index Is Calculated • 4.Choose a Base Year and Compute the Index(选择基年,计算价格指数): Designate one year as the base year Compute the index by dividing the price of the basket in one year by the price in the base year and multiplying by 100