409.09% is the change from 99 to 504
Calculation steps:
[( 504 - 99 ) ÷ 99] x 100 = 409.09%
Formula
Percentage change = [(504 - 99) / 99] x 100
Subtract the new number by the original number
504 - 99 = 405
405 ÷ 99 = 4.090909090909091
4.090909090909091 x 100 = 409.09%