July 13, 1999 (The Editor’s Desk is updated each business day.)
Transportation prices and the new
research series
Upward adjustments to measured changes in transportation
prices occurred as often as downward adjustments in the new CPI research series. In
contrast, the research series for the overall Consumer Price Index was adjusted downward
in every year except one in the 1978-98 study period.
[Chart data—TXT]
Transportation inflation was adjusted downward in 9 years, when comparing the research
series and the official series. There also were 9 years with upward adjustments, and 3
years in which the rates of price changes were identical in the two series. The net effect
of the adjustments over the 1978-98 period was about zero—the average annual growth
rate of transportation prices was actually 0.03 percentage point higher in the research
series.
Several offsetting changes contributed to the tiny net effect on transportation prices.
The research series reflects downward adjustments for changes in the quality of used cars
and for improved index-number formulas. However, there were upward adjustments due to
deleting the index for automobile finance charges and to backing out a prior adjustment
for changes in automobile quality involving mandated pollution controls.
The BLS Consumer Price Index program produces CPI data. BLS
has made numerous improvements to the CPI over the years, which have increased the
accuracy of the index; however, the official historical price indexes are not adjusted to
reflect the improvements. Find more information on the CPI research series in "CPI research series using current methods,
1978-98," by Kenneth J. Stewart and Stephen B. Reed, Monthly Labor Review,
June 1999. It is important to note that the CPI research series has certain limitations
and that it is subject to revision. Annual percent changes are December-to-December
changes. Also, note that in the chart positive differences reflect downward adjustments in
the research series and negative differences reflect upward adjustments.
Of interest
Spotlight on Statistics: National Hispanic Heritage Month
In this Spotlight, we take a look at the Hispanic labor force—including labor force participation, employment and unemployment, educational attainment, geographic location, country of birth, earnings, consumer expenditures, time use, workplace injuries, and employment projections.
.
Read more »