2 January 2008 the Dow Jones Industrial Average (DJIA) closes at 13043 (omitting decimals). I calculate that the annual growth rate for the DJIA from 13 December 1956 to 13 December 2006 (50 years) is 6.66 %. If I calculate 6.66 % growth for the next hundred years then the DJIA value is 8,232,570 at the beginning of year 2108. In ten years (year 2018) the DJIA calculates to be 24,854. Year 2028, 47,360. 2008 13,043 2009 13,912 2010 14,838 2011 15,826 2012 16,880 2013 18,005 2014 19,204 2015 20,483 2016 21,847 2017 23,302 2018 24,854 2019 26,509 2020 28,275 2021 30,158 2022 32,166 2023 34,308 2024 36,593 2025 39,031 2026 41,630 2027 44,403 2028 47,360 2038 90,245 2048 171,965 2058 327,685 2068 624,413 2078 1,189,839 2088 2,267,273 2098 4,320,357 2108 8,232,570
you are assuming it will grow that rate going forwards. The most likely reason you are wrong is that the USD wont survive that long (which is what your pricing it in).