-69.22% is the change from 640 to 197
Calculation steps:
[( 197 - 640 ) ÷ 640] x 100 = -69.22%
Formula
Percentage change = [(197 - 640) / 640] x 100
Subtract the new number by the original number
197 - 640 = -443
-443 ÷ 640 = -0.6921875
-0.6921875 x 100 = -69.22%