697.5% is the change from 80 to 638
Calculation steps:
[( 638 - 80 ) ÷ 80] x 100 = 697.5%
Formula
Percentage change = [(638 - 80) / 80] x 100
Subtract the new number by the original number
638 - 80 = 558
558 ÷ 80 = 6.975
6.975 x 100 = 697.5%
Example