306.06% is the change from 99 to 402
Calculation steps:
[( 402 - 99 ) ÷ 99] x 100 = 306.06%
Formula
Percentage change = [(402 - 99) / 99] x 100
Subtract the new number by the original number
402 - 99 = 303
303 ÷ 99 = 3.0606060606060606
3.0606060606060606 x 100 = 306.06%