-34.29% is the change from 974 to 640
Calculation steps:
[( 640 - 974 ) ÷ 974] x 100 = -34.29%
Formula
Percentage change = [(640 - 974) / 974] x 100
Subtract the new number by the original number
640 - 974 = -334
-334 ÷ 974 = -0.34291581108829566
-0.34291581108829566 x 100 = -34.29%