NEW YORK – Most stocks advanced Tuesday, while the Standard & Poor’s 500 Index posted its smallest move since August, as optimism about third-quarter corporate earnings overshadowed concern that Europe’s debt crisis is worsening.

Alcoa, the biggest U.S. aluminum producer, rose 2.1 percent ahead of its results. Apple, Bank of America and Caterpillar added at least 1.4 percent to pace gains among companies most tied to the economy. Mosaic jumped 4.3 percent as Credit Suisse said valuations for fertilizer shares are attractive. AMR rose 7.1 percent as American Airlines joined its bigger U.S. peers with deeper seating cuts.

Almost seven stocks rose for every five that fell on U.S. exchanges. The S&P 500 added 0.1 percent to 1,195.54. The benchmark gauge traded within a 1 percent range between its high and low level for the day, the narrowest range since July 26. The Dow Jones Industrial Average retreated 16.88 points, or 0.2 percent, to 11,416.30.

“The markets have shrugged off some of the pessimism,” Peter Tuz, president of Chase Investment Counsel in Charlottesville, Va., said in a telephone interview. “Beginning with Alcoa today, only time will tell if earnings won’t be quite as bad as we all feared. There’s a bit of catch-up going on. We’re seeing a recovery in groups that have really taken it on the chin.”

The S&P 500 has fallen as much as 19 percent from its three-year high in April through Aug. 3, on a closing basis, amid concern that Europe’s crisis would worsen an economic slowdown. Gauges of financial, commodity and industrial shares in the index slumped more than 26 percent during that period.

Earnings per share for the S&P 500, excluding financial companies, rose 14 percent in the third quarter, according to analysts’ estimates compiled by Bloomberg. Still, it’s the smallest gain since the end of 2009, the data showed.

Alcoa, the first company of the Dow to report results for the third quarter, climbed 2.1 percent to $10.30 in regular trading. The shares tumbled 4.5 percent to $9.84 at 4:36 p.m. EDT, after the earnings were released.

Excluding restructuring costs, earnings were about 14 cents a share, New York-based Alcoa said. The average estimate of analysts was 22 cents.