7937.5% is the change from 8 to 643
Calculation steps:
[( 643 - 8 ) ÷ 8] x 100 = 7937.5%
Formula
Percentage change = [(643 - 8) / 8] x 100
Subtract the new number by the original number
643 - 8 = 635
635 ÷ 8 = 79.375
79.375 x 100 = 7937.5%
Example