But 2017 was weird. There were five such days in 2016, six in 2015 and four in 2014. In 2011, there were 21 trading days in which the S.&P. fell by more than 2 percent, nearly two per month. A bit of overreaction is as natural as people in normally dry Los Angeles having trouble driving in the rain.

There’s no doubt that the 7.8 percent drop since Jan. 26 is substantial; it represents nearly $2 trillion of paper wealth. But you find some better news underneath that unpleasant fact when you look at what has happened in the bond market while stocks have been falling.

Frequently when investors become more pessimistic about the economy, stocks fall and the yield on bonds falls as well. That pattern happens because a weaker economy implies not just lower corporate profits (hence the falling stock indexes) but lower inflation and continued low interest rates from the Federal Reserve (which implies bonds are more valuable and their yield should fall).

But that hasn’t been the pattern in this downturn. During the stock market swoon on Friday, the yield on 10-year Treasury bonds rose sharply. Bond market measures of future inflation rose. Even after that trend reversed during the Monday sell-off, interest rates are still higher after this drop in markets (2.7 percent at Monday’s close) than they were before (2.66 percent on Jan. 26).

Instead of reflecting economic pessimism, this stock market sell-off seems rooted in a form of optimism — that employers will have to pay higher wages, cutting into profits, and that higher inflation will cause the Fed to raise rates faster than had been assumed. Throw in some worry that markets were getting a little overheated and you have a recipe for the downturn we’ve just witnessed.

In other words, this bad news for stock investors seems to be driven in part by good news for workers. And since most people earn more money from their jobs than from their investment portfolios, that’s a trade a lot of people would be happy to take.