If you put your money into an S&P 500 index fund in 2006 and reinvested dividends every distribution, you would have 6.89% annual return even taking into account recent recessions. In other words, if you had $10,000 in your 401(k) in 2006 and stopped adding any payroll to it, it would be worth over $19,000 now. If your 401(k) isn't in an index fund, it might be worth switching it into one rather than keeping it in a managed fund that charges higher expense ratios, but has worse returns.