what is the best sandp 500 5 year period

The highest closing price for the S&P 500 (GSPC) in a year all-time was $6,753.72, this year. It is up 14.4% for the year. The latest price is $6,723.29.

Daily pricing data for the S&P 500 dates back to 12/30/1927, and may be incomplete.