USAFGuy,
The attached spreadsheet allows you to calculate the returns forvarious TSP fund allocations since 1988. Just modify the allocation percentages. I've already entered the 1/3, 1/3, 1/3 values for the C, S, and I funds. However, you'll probably want to "game" other allocations. The 2004 return values are current as of 12/8.
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