Over the last 50 years, every time that job growth has been as meager as it has been over the last four months, the economy has been headed toward recession, in a recession or in the immediate aftermath of one. From early 2010 through this spring, by contrast, employment was growing fast enough to make the economy look as if it were in a recovery, albeit a modest one.

“The chances that we are in something that is going to feel like a recession are close to 100 percent,” said Joshua Shapiro of MFR Inc. in New York, who has diagnosed the economy more accurately than many other forecasters lately. “Whether we reach the technical definition” — which is determined by a committee of academic economists and based on gross domestic product, employment and other factors — “I think is probably close to 50-50.”…