-7.29% is the change from 686 to 636
Calculation steps:
[( 636 - 686 ) ÷ 686] x 100 = -7.29%
Formula
Percentage change = [(636 - 686) / 686] x 100
Subtract the new number by the original number
636 - 686 = -50
-50 ÷ 686 = -0.0728862973760933
-0.0728862973760933 x 100 = -7.29%