The year is 1961. A single GFLOPS is valued at $1.1 trillion.
The year is now 2010. A single GFLOPS is valued at less than 13 cents.
ATi's HemlockXT HD5970 performs up to 4.64TFLOPS.
This is a 49-year window gap. The price of a single GFLOPS decreased by around $22.45 billion per year (assuming an obviously incorrect linear relationship).