319.17% is the change from 120 to 503
Calculation steps:
[( 503 - 120 ) ÷ 120] x 100 = 319.17%
Formula
Percentage change = [(503 - 120) / 120] x 100
Subtract the new number by the original number
503 - 120 = 383
383 ÷ 120 = 3.191666666666667
3.191666666666667 x 100 = 319.17%