1001.11% is the change from 90 to 991
Calculation steps:
[( 991 - 90 ) ÷ 90] x 100 = 1001.11%
Formula
Percentage change = [(991 - 90) / 90] x 100
Subtract the new number by the original number
991 - 90 = 901
901 ÷ 90 = 10.011111111111111
10.011111111111111 x 100 = 1001.11%