BEA current and historical data: national, international, and regional data

Survey of Current Business,  Dec, 2004  

Tags: BEA Systems Inc.

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For quarters and months, NIPA estimates are presented at annual rates, which show the value that would be registered if the rate of activity that is measured for a quarter or for a month were maintained for a full year. Annual rates are used so that periods of different lengths--for example, quarters and years--may be more easily compared. These annual rates are determined simply by multiplying the estimated rate of activity by 4 (for quarterly data) or by 12 (for monthly data).

For most quarterly NIPA estimates, percent changes in the estimates are also expressed at annual rates. Calculating these changes requires a variant of the compound interest formula:

r = [[([x.sub.t]/[x.sub.o]).sup.m/n] - 1] x 100

where r is the percent change at an annual rate; [x.sub.t] is the level of activity in the later period; [x.sub.o] is the level of activity in the earlier period; m is the periodicity of the data (for example, 1 for annual data, 4 for quarterly data, or 12 for monthly data); and n is the number of periods between the earlier periods and the later periods (that is, t-O).

Quarterly and monthly NIPA estimates are seasonally adjusted if necessary. Seasonal adjustment removes from the time series the average effects of variations that normally occur at about the same time and in about the same magnitude each year--for example, weather, holidays, and tax payment dates. After seasonal adjustment, cyclical and other short-term changes in the economy stand out more clearly.

"Table 1. Reconciliation of Changes in BEA-Derived Compensation Per Hour With BLS Average Hourly Earnings" is being revised to reflect the results of the comprehensive revision of the national income and product accounts. It will be published in an upcoming issue of the SURVEY.