The Effects of New Goods and Substitution on the Korean CPI as a Measure of Cost of Living

This paper estimates upper-level substitution and new-goods bias in the Korean Consumer Price Index (CPI) from the early 1990s to the mid 2000s. It has been estimated that the upper-level substitution bias in the CPI alone increased the inflation rate by 0.51 percentage points per year over the 13-year period between 1990 and 2002. The new-goods bias further increased the inflation rate by 0.17 and 0.13 percentage points per year between 1990-1995 and 1995-2000 respectively. The Chained Laspeyres index series that is based on annually-updated weights has been found to correct less than half of the upper-level substitution bias.