685.19% is the change from 81 to 636
Calculation steps:
[( 636 - 81 ) ÷ 81] x 100 = 685.19%
Formula
Percentage change = [(636 - 81) / 81] x 100
Subtract the new number by the original number
636 - 81 = 555
555 ÷ 81 = 6.851851851851852
6.851851851851852 x 100 = 685.19%