In a blog post published Friday, the Bureau of Economic Analysis listed a series of alterations it will make in seasonally adjusting data used to calculate economic growth.
The changes will be implemented with the release of the initial second-quarter GDP estimate on July 30, the BEA said. Although the agency adjusts its figures for seasonal variations, growth in any given first quarter still tends to be weaker than in the remaining three, economists have found, a sign there may be some bias in the data. It’s a phenomenon economists call “residual seasonality.”
The agency is exploring ways to address possible issues in measures of federal government defense spending, where research has shown that first- and fourth-quarter growth rates are lower on average, the BEA said, reiterating a statement given to Bloomberg published May 18.
Additionally, the BEA is reviewing all series that figure into the GDP calculations to find and fix any leftover biases that exist within its current methodology.