-50.87% is the change from 631 to 310
Calculation steps:
[( 310 - 631 ) ÷ 631] x 100 = -50.87%
Formula
Percentage change = [(310 - 631) / 631] x 100
Subtract the new number by the original number
310 - 631 = -321
-321 ÷ 631 = -0.508716323296355
-0.508716323296355 x 100 = -50.87%