Foreign Trade

Changes to Chained (2005) Dollar Series

Frequently Asked Questions

What are Constant Dollar import and exports?

Constant Dollar is a process that adjusts the United States import and export trade data so that they may be compared to the trade totals of previous years without being affected by inflation.

Why is the Census Bureau seasonally adjusting chained dollar data?

The seasonal adjustments will improve the overall quality of the prices and Chained Dollars, and will also improve the consistency between the Bureau of Economic Analysis and the Census Bureau’s chained dollar data.

Why are the prices for import petroleum being seasonally adjusted? Are the prices being calculated differently?

Unit prices are still used to calculate the prices, but the values and quantities used to develop prices are now being seasonally adjusted. Also, four prices are calculated – one for each end-use code – instead of on common price for all.

Will the seasonally adjusted prices affect the Chained Dollars?

Yes. Published chained dollars are based on seasonally adjusted fixed-weighted data. The intent of adjusting the deflator is to remove seasonality in the Chained dollars. However, there is no guarantee that all seasonality will be removed in the aggregate level chained dollar data.

Does Census plan to continue producing the Chained Dollars based on non-seasonally adjusted prices and a single import petroleum deflator?

The seasonally adjusted Chained Dollars data will replace the previously unadjusted data in all published tables. For time-series purposes, 2012 real (chained dollar) series calculated using not-seasonally adjusted deflators will be made available upon request.

Will prior years of chained dollar data calculated using the new methodology be available?

Yes. Revised chained dollar data prior to 2010 will be made available when the 2012 annual revisions are published on June 8, 2012.