-53.75% is the change from 640 to 296
Calculation steps:
[( 296 - 640 ) ÷ 640] x 100 = -53.75%
Formula
Percentage change = [(296 - 640) / 640] x 100
Subtract the new number by the original number
296 - 640 = -344
-344 ÷ 640 = -0.5375
-0.5375 x 100 = -53.75%