The Sahm rule and the economy's 'statistical regularities'

A version of this post first appeared on TKer.co.

Just because something happened a bunch of times in the past doesn’t mean it must happen again in the future.

This is what Fed Chair Jerome Powell communicated when asked about the “Sahm Rule” recession indicator, which has revealed that recessions historically started when the three-month moving average of the unemployment rate rose 0.5 percentage points or more above its 12-month low.

“A statistical regularity is what I call it,” Powell said on Wednesday. “It's not like an economic rule, where it's telling you something must happen.”

Claudia Sahm, the economist whom the indicator is named after, would agree.

“Indicators of economic downturns like the Sahm rule are empirical regularities from the past, not laws of nature,” Sahm wrote last November.

On Friday, we learned that the unemployment rate rose to 4.3% in July. This caused the three-month moving average of the unemployment rate to breach that 0.5 percentage point threshold for the first time in this economic cycle.

Sahm has been arguing that her namesake indicator triggering could be a false positive due lingering pandemic-related economic distortions.

“The Sahm rule is likely overstating the labor market's weakening due to unusual shifts in labor supply caused by the pandemic and immigration,” Sahm recently said.

The economy is more than a few metrics

All of this speaks to TKer’s Rule No. 1 of analyzing the economy: Don’t count on the signal of a single metric.

It’s a lesson that’s been learned following false positive recession signals from the yield curve and the Conference Board’s Leading Economic Index.

The economy is complex with countless numbers of moving parts, and sometimes some of those parts will be behaving so abnormally that it will force time-tested indicators to break down.

For example, the current economic cycle has come with an unusually high number of job openings: a sign of abnormally strong demand. At its peak in March 2022, there was an unprecedented two job openings per unemployed person.

Over the past two years, this excess demand for jobs had people controversially believing that it would be possible to bring down inflation without a large rise in unemployment. Because, basically it was those extra job listings that were emboldening workers to press for higher pay, and employers obliged because of booming demand. All the Fed had to do was cool the economy just enough that demand would come down just enough for employers to take down those job listings, the argument went, which in turn would help inflation to come down.