The difference between junk bond yields and the rate on quality-rated corporate debt suggests that default risks are rising—”an ominous signal for the stock market,” says the Lakshman Achuthan of the Economic Cycle Research Institute. This according to a recent CNBC article.

Achuthan, a business cycle expert, describes the increasing spread as being “troublesome” and, according to the article, “has been attacking Wall Street for being too optimistic about 2018. He’s been warning corporate clients and fund managers that it could cause another downdraft in an easily spooked market.”

According to Achuthan, even if tax cuts serve to boost economic growth, it would only be by a half percent or so. “If you’re looking at a slowdown of a couple percent, it’s not enough to offset it,” he says. Still, he is not predicting a collapse: “There’s no recession in sight. But everybody is kind of extrapolating the strength, the momentum—to use a word that’s out there from 2017 into 2018. You’re got the tax cuts on top so ‘it must be good’- but actually the cycle itself seems to be decelerating this year.”