Wall Street is flirting with a record again as U.S. stock indexes drift in mixed trading on Tuesday. The S&P 500 was virtually unchanged in late trading and sitting just below its all-time closing high set last month,

However, the S&P 500 ( ^GSPC -0.01%) is generally considered the best barometer for the overall U.S. stock market due to its scope and diversity. Read on to see the S&P 500's average return over the last decade, and to learn what Wall Street expects in the future.

Wall Street edged back from an all-time high following mixed profit reports from big companies. The S&P 500 barely budged on Friday and slipped by a hair, a day after rallying within 0.1% of its record set last month.

Stocks are drifting lower although still near a record high as a holiday-shortened week gets off to a sluggish start. The S&P 500 edged 0.1% lower in Tuesday afternoon trading and is just below its all-time closing high set last month.