901.01% is the change from 99 to 991
Calculation steps:
[( 991 - 99 ) ÷ 99] x 100 = 901.01%
Formula
Percentage change = [(991 - 99) / 99] x 100
Subtract the new number by the original number
991 - 99 = 892
892 ÷ 99 = 9.01010101010101
9.01010101010101 x 100 = 901.01%