>but the way to do it is probably to come up with a certain basket I don't get it. Tell them what to buy? The official figures are based on a basket determined

>but the way to do it is probably to come up with a certain basket I don't get it. Tell them what to buy? The official figures are based on a basket determined by surveying people. That is the point. It sounds like you are saying the problem with the government CPI is that it's not predetermined? "The Quarterly Interview Survey is designed to collect data on large and recurring expenditures that consumers can be expected to recall for a period of 3 months or longer, such as rent and utilities, and the Diary Survey is designed to collect data on small, frequently purchased items, including most food and clothing. Together, the data from the two surveys cover the complete range of consumers’ expenditures." See https://www.bls.gov/cex/ https://www.bls.gov/cex/