NEW YORK — Investors heard some more good news about the economy today but locked in profits anyway following huge gains earlier in the week.

Upbeat reports on the job market and retail sales initially sent stocks higher, but the gains eroded by mid-morning as traders asked "What's next?" and trimmed their holdings following the 4.8 percent gain so far this week in the Standard & Poor's 500 index.

"This is a market that is starting to bake in a lot of positive surprises," said Craig Peckham, a market strategist at Jefferies & Co.

The selling comes ahead of the formal release of results from the government's "stress tests" of bank balance sheets after the closing bell. News reports have already given investors a decent idea of what to expect so analysts aren't predicting big surprises.

A massive two-month rally has left the S&P 500 index in the black for the year and up more than 30 percent from 12-year lows reached in early March. Analysts said it wasn't surprising the market would take a break after such big gains.

Technology shares posted the biggest losses today after security software maker Symantec posted weaker-than-expected results. Retailers were mixed even after many of them, including Wal-Mart, reported better-than-expected April sales.