Improving the preliminary values of the chained CPI-U

摘要

This paper employs a constant-elasticity of substitution (CES) index formula to improve the accuracy of the preliminary values of the Chained Consumer Price Index for All Urban Consumers (C-CPI-U). Using the CES behavioural model, I present estimates of the overall extent of consumer response to relative price changes exhibited in Consumer Expenditure Survey data for 1999-2008. The associated parameter estimates are then used to develop CES forecasts of the final C-CPI-U index values. Simulations demonstrate that use of the CES approach over the last several years would have resulted in smaller index revisions between the preliminary and final C-CPI-U releases. Looking to the future, CES-based preliminary estimates could increase the usefulness of the C-CPI-U to government programs and other users.