2415% is the change from 20 to 503
Calculation steps:
[( 503 - 20 ) ÷ 20] x 100 = 2415%
Formula
Percentage change = [(503 - 20) / 20] x 100
Subtract the new number by the original number
503 - 20 = 483
483 ÷ 20 = 24.15
24.15 x 100 = 2415%
Example