Beginning with its very first issue in May 1915, the Federal Reserve’s Bulletin was the place to find a growing body of statistics on US economic performance. Four years later, monthly data was being put together on the physical volumes of trade. From these, in 1922, the precursor to what we know today as Industrial Production was formed.

The index and its components have changed considerably over its near-century of operative history. But it’s the length of the series and its application that continues to draw serious scrutiny. Contraction in IP has almost always been associated with declared recession. False positives are few.

For these reasons, the Economists who have tasked themselves with “officially” (its not a government declaration, rather one made within the Economics community that is treated as declarative because it is believed acceptable by the profession) dating the business cycle use IP along with only a few other indications to make their determination. If a cycle peak means a broad-based, widespread economic downturn, then IP’s signal is as the singular proxy for the very important contribution, or subtraction, of US industry.

Even in those cases where Industrial Production may have turned lower outside of official recession, nearly all have been a matter of timing. In isolated instances, IP may not have been enough on its own to trigger a cycle dating but has always described a slowdown or downturn reaching considerable and serious proportions.

It is not, however, a static statistic. Rarely do you find any that are. Revisions are a constant intrusion of modern economic gathering and measuring. Large-scale sampling is always preferred but it takes time.

Annual benchmark revisions for IP completed last month but accompanying the latest release demonstrate yet again the difficulties in situations like the current “cycle.” Statistics like these are supposed to be objective, but they contain within them several key subjective judgments (trend-cycle the biggest). For yet another benchmark year, IP is pushed downward.