6400% is the change from 8 to 520
Calculation steps:
[( 520 - 8 ) ÷ 8] x 100 = 6400%
Formula
Percentage change = [(520 - 8) / 8] x 100
Subtract the new number by the original number
520 - 8 = 512
512 ÷ 8 = 64
64 x 100 = 6400%
Example