Wall Street edged back from its all-time high on Friday, as U.S. stock indexes drifted following mixed profit reports from big companies. The S&P 500 barely budged and slipped by less than 0.1%, a day after rallying within 0.

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 is flirting with a record on Friday, as U.S. stock indexes drift following some mixed profit reports from big companies. The S&P 500 rose 0.1% in afternoon trading, a day after rallying within 0.