37.66% is the change from 640 to 881
Calculation steps:
[( 881 - 640 ) ÷ 640] x 100 = 37.66%
Formula
Percentage change = [(881 - 640) / 640] x 100
Subtract the new number by the original number
881 - 640 = 241
241 ÷ 640 = 0.3765625
0.3765625 x 100 = 37.66%