“You’re getting a market that got close to a 10% correction, so you’re starting to see buyers step in to buy the dip,” Lyon said.

Fund managers also tend to make moves toward the end of a quarter to bolster their portfolios, another reason for the end-of-the-week buying spree, he said.

The Dow Jones Industrial Average was up 337 points, or 1.3%, at 27,155, as of 3:36 p.m. Eastern time Friday, and the Nasdaq composite was 2.2% higher.

Smaller stocks were also higher, and the Russell 2000 index of small-cap stocks was up 1.8%.

Stocks have struggled this month amid a long list of concerns. Chief among them is that stocks may have gotten too expensive following their record-breaking run through the summer, after storming 60% higher. Critics say Big Tech stocks in particular rose too high, even after accounting for their tremendous growth even as the coronavirus weakened the economy.

“This week, and the month of September, is really what we’re calling the give-back month,” Lyon said. ”(Stock) valuations got expensive and this is a natural settling of the market, kind of giving back some of those advance returns that were probably ahead of themselves.”

Big Tech stocks were higher after falling earlier. Apple was up 3.5%. Microsoft rose 2.3%, and Google’s parent company was up 1.2%.

Traders also bid up shares in cruise lines. Norwegian Cruise Line was among the biggest gainers in the S&P 500, vaulting 12.5%. Carnival jumped 9.2% and Royal Caribbean Group climbed 7.5%.