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Among individual stocks, a handful of medical companies were the top decliners in the S&P 500.

Intuitive Surgical, a maker of robotic surgery systems, plunged $88.19, or 18 percent, to $411.89 after the company forecast disappointing second-quarter sales late Monday. Laboratory Corp. of America fell $4.27, or 4.3 percent, to $95.86. Varian Medical Systems, a maker of medical devices and software for treating cancer, fell $2.06, or 3 percent, to $66.14.

IBM fell $3.06, or 1.6 percent, to $191.90 after a Goldman Sachs analyst lowered his rating and cut his price target on the stock, saying the company may face more pressure in the near term in emerging markets.

The Dow Jones transportation index rose the most among major U.S. indexes, jumping 148 points, or 2.4 percent, to 6,446. It was led by Alaska Air Group’s stock, which rose 7 percent. The airline said in regulatory filing late Monday that it expects an additional $50 million a year in revenue from raising its baggage and ticket change fees. FedEx also surged 6 percent to $104.80 on speculation that Bill Ackman’s hedge fund, Pershing Square, could make an investment in the company.

Corporate America’s quarterly results should give Wall Street fresh fodder after investors and traders spent most of June trying to figure out where the Fed was headed with its economic stimulus program.

The central bank has been buying $85 billion in bonds a month to keep interest rates low and encourage borrowing and spending. Comments from Fed Chairman Ben S. Bernanke that the central bank planned to reduce the stimulus prompted the stock market to pull back from record levels reached in late May.

Even so, stock markets are likely to become more volatile before the Fed starts to ease and investors try and assess by when and how quickly the central bank will cut the stimulus, said Dean Junkas, chief investment officer of Wells Fargo Private Bank.

“More volatility in the second half of the year is what we’re expecting, as this plays out,” Mr. Junkas said.

Stocks have since recovered most of their losses, and the S&P 500 is now just 1 percent below its May 21 record of 1,669, having fallen almost 6 percent to 1,573 June 24.

In government bond trading, the yield on the 10-year Treasury note was little changed at 2.64 percent early Tuesday. The yield has pulled back after surging to 2.74 percent Friday, its highest level in almost two years, after the government reported strong hiring for June.

In commodities trading, the price of oil rose 17 cents, or 0.2 percent, to $103.33 a barrel. Gold rose $12, or 1 percent, to $1,246.90.

Among other stocks making big moves:

• WD-40 rose $3.13, or 5 percent, to $60.77 after the maker of maintenance products reported earnings that beat financial analysts’ forecasts.

• Barnes and Noble rose 64 cents, or 3.6 percent, to $18.32 after the bookseller said Monday its CEO is leaving after three years. The company didn’t name a replacement.