Which time? :-) It goes up, it goes down....
More seriously, the answer to this is going to vary dramatically depending upon the composition of your portfolio, whether (and to what extent) you are adding fresh funds to it, and what the overall markets are doing. For example, on Jan. 9, 1998, the S&P was at 927.69. On July 24, 1998, it was at 1140.80; thus, if you had 850K in January, it would have been at 1,045,263 in that time. Then again, if you weren't adding money, you wouldn't have stayed there forever. On October 4, 2002, S&P was at 800.58 and on March 6, 2009, it was at 683.38.
(I grant just using the index is lazy and misleads a bit because it ignores dividends and, more importantly, influxes of money during the years.)