2490% is the change from 20 to 518
Calculation steps:
[( 518 - 20 ) ÷ 20] x 100 = 2490%
Formula
Percentage change = [(518 - 20) / 20] x 100
Subtract the new number by the original number
518 - 20 = 498
498 ÷ 20 = 24.9
24.9 x 100 = 2490%
Example