My Vanguard Performance - The Lost Decade

You might have heard of the lost decade. The cumulative total return for Vanguard's s&p 500 index fund for the last ten years (ending jan 31, 2010) is -8.48%, according to vanguard. (Appears to include reinvested dividends and management fees, see here). Hence the phrase the lost decade. My vanguard portfolio cumulative total return from Jan 1, 2000 to Jan 1, 2010 was 67%.