37.19% is the change from 640 to 878
Calculation steps:
[( 878 - 640 ) ÷ 640] x 100 = 37.19%
Formula
Percentage change = [(878 - 640) / 640] x 100
Subtract the new number by the original number
878 - 640 = 238
238 ÷ 640 = 0.371875
0.371875 x 100 = 37.19%