489.9% is the change from 99 to 584
Calculation steps:
[( 584 - 99 ) ÷ 99] x 100 = 489.9%
Formula
Percentage change = [(584 - 99) / 99] x 100
Subtract the new number by the original number
584 - 99 = 485
485 ÷ 99 = 4.898989898989899
4.898989898989899 x 100 = 489.9%