Key PointsThe S&P 500 has consistently outperformed most stocks and actively managed funds.It’s still a safe place to park any cash you don’t need right away. Motley Fool Issues Rare "Total Conviction" Buy Alert › The S&P 500 (SNPINDEX: ^GSPC) has generated an average annual total return of about 10% since its inception in 1957. However, the index has also gone through some wild swings over the past seven decades -- and those downturns shook out…