26.98% is the change from 504 to 640
Calculation steps:
[( 640 - 504 ) ÷ 504] x 100 = 26.98%
Formula
Percentage change = [(640 - 504) / 504] x 100
Subtract the new number by the original number
640 - 504 = 136
136 ÷ 504 = 0.2698412698412698
0.2698412698412698 x 100 = 26.98%