-24.69% is the change from 640 to 482
Calculation steps:
[( 482 - 640 ) ÷ 640] x 100 = -24.69%
Formula
Percentage change = [(482 - 640) / 640] x 100
Subtract the new number by the original number
482 - 640 = -158
-158 ÷ 640 = -0.246875
-0.246875 x 100 = -24.69%