But when it comes to the recent 1.9 percent decline reported in the first quarter of 2015, and the massive near-5 percent plunge a year ago, there could be at least some statistical noise at work. Focusing on nonfarm productivity, the gauge most often followed by economists, CNBC found that it has averaged 1.1 percent in the first quarter over the past 30 years, compared with overall productivity growth of 2 percent. Over the past six years, the efficiency record of the country in the first quarter has been nothing short of abysmal, shrinking 1.2 percent on average since 2010, while all the other quarters show some growth. In four of the past six years, first quarter productivity has been flat or negative.
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Of the 20 biggest quarterly declines in productivity over the past three decades, 11 of them have been in the first quarter, including the top three most severe. The single worst decline was the 4.7 percent productivity plunge in the first quarter of 2014.
In April, CNBC revealed that the gross domestic product data, the broadest and most-followed measure of economic growth for the country, was potentially flawed because of unexplained and persistent weakness in the first quarter. First-quarter GDP data averaged 1.9 percent while the economy overall grew 2.7 percent. Economists told CNBC that such a finding shouldn't exist if data were properly adjusted for seasonal patterns.
A string of recently weak first quarters have confounded Fed officials and investors by raising ongoing concerns about the strength of the economic recovery.
The Bureau of Economic Analysis, which compiles GDP, has since acknowledged problems in the data and announced "a multi-pronged action plan to improve its estimates" including reviewing existing seasonal adjustments. Data for the past three years is expected to include new estimates with the July 30 release of second-quarter GDP.