Monthly data, seasonally adjusted
Consumer Price Indices for Transportation, U.S. City Average
|All Items||Transportation||Private transportation||Public transportation|
NOTES: The consumer price index for a specific item is a weighted average of the prices for the individual components of the item. The weights are determined by the expenditure shares of the individual components based on a survey of consumer expenditure during the base year(s). The base year price is then normalized to 100. For some items, BLS establishes weights using several years of consumer expenditure surveys in order to smooth out the effects of short-term price shocks and of the business cycle. Weights formed using several years will give a more accurate measure of typical consumer expenditure patterns.
Private transportation is a weighted average of the prices for new and used motor vehicles, motor fuels, motor vehicle parts and equipments, motor vehicle maintenance and repair, motor vehicle insurance, and motor vehicle fees (state and local registration and license fees, parking and other fees).
Public transportation is a weighted average of the prices for airline fares, intercity bus fares, intercity train fares, ship fares, intracity transportation (intracity mass transit, taxi fares, and car and van pools), and other public transportation.
The base period of the original index is 1982-84. January 1992 is set to be the new reference point (=100) by dividing the values of the original index by the value of January 1992 in the original index. It is important to point out that this process changes only the reference point, and not the base period of the index because the weight structure of the index did not change.
The Consumer Price Index (CPI) tracks the price of a market basket of goods and services purchased by U.S. households over time. Both monthly and annual changes are reported in the tables for the CPI in order to facilitate comparison with other series.
SOURCE: U.S. Department of Labor, Bureau of Labor Statistics; available at: http://www.bls.gov/cpi/; as of September 2007.