509.09% is the change from 99 to 603
Calculation steps:
[( 603 - 99 ) ÷ 99] x 100 = 509.09%
Formula
Percentage change = [(603 - 99) / 99] x 100
Subtract the new number by the original number
603 - 99 = 504
504 ÷ 99 = 5.090909090909091
5.090909090909091 x 100 = 509.09%