Stocks Log First Weekly Loss Since Early May

Traders have been anticipating a pullback after such big gains in such a short period. Usually, a 40 percent move like the one in the S&P 500 index takes years to develop, not months.

"It's not going to be a one-way ride," said Keith Walter, portfolio manager of Artio Global Equity Fund.

Analysts are divided over whether the market's pullback this week has more to go, or if it can now move higher after back-to-back weeks of relatively sideways movement; Last week all the major indexes rose less than 1 percent. Many predict choppy trading well through the summer, when there is typically less volume, and as the market heads into earnings season in July.

Next week will bring reports on existing home sales and durable goods orders, among others. Investors will also be looking to the Federal Reserve for any clues on its monetary policy going forward as the central bank conducts a two-day policy meeting.

Bond prices rose slightly after sliding Thursday ahead of a spate of auctions next week. The yield on the benchmark 10-year Treasury note fell to 3.78 percent from 3.81 percent late Thursday.