-99% is the change from 901 to 9
Calculation steps:
[( 9 - 901 ) ÷ 901] x 100 = -99%
Formula
Percentage change = [(9 - 901) / 901] x 100
Subtract the new number by the original number
9 - 901 = -892
-892 ÷ 901 = -0.9900110987791343
-0.9900110987791343 x 100 = -99%