57.5% is the change from 320 to 504
Calculation steps:
[( 504 - 320 ) ÷ 320] x 100 = 57.5%
Formula
Percentage change = [(504 - 320) / 320] x 100
Subtract the new number by the original number
504 - 320 = 184
184 ÷ 320 = 0.575
0.575 x 100 = 57.5%
Example