This article presents quarterly estimates of the alternative measures of change in real output and prices that BEA introduced in April 1992.l It also updates the annual estimates for 1988-90 to incorporate the results of the annual revision of the national income and product accounts (NIPA's) in July 1992 and extends the annual estimates to 1991.2 The alternative measures, which supplement BEA's featured fixed-weighted measures, are especially useful for studies of long-term economic growth, for comparisons of business cycles, and for gauging the effect of changes in the economy's relative price structure on the measurement of real gross domestic product ( GDP). Beginning with the May issue of the Survey of Current Business, BEA will publish current quarterly estimates of the alternative measures in the regular presentation of the preliminary and final NIPA estimates.