The U.S. economy isn’t in a recession yet, but the number of industries cutting back on headcount is concerning, and future revisions to jobs data could show employment is already falling, according to Moody’s Analytics chief economist Mark Zandi.

In a series of X posts on Sunday, he followed up his warning from last weekend that the economy is on the brink of a recession.

This time, Zandi pointed out that the start of a recession is often unclear until after the fact, noting that the National Bureau of Economic Research is the official arbiter of when one begins and ends.

According to the NBER, a recession involves “a significant decline in economic activity that is spread across the economy and lasts more than a few months.” It also looks at a range of indicators, including personal income, employment, consumer spending, sales, and industrial production.

Zandi said payroll employment data is by far the most important data point, and declines for more than a month consecutively would signal a downturn. While employment hasn’t started falling yet, it has barely grown since May, he added.