800% is the change from 99 to 891
Calculation steps:
[( 891 - 99 ) ÷ 99] x 100 = 800%
Formula
Percentage change = [(891 - 99) / 99] x 100
Subtract the new number by the original number
891 - 99 = 792
792 ÷ 99 = 8
8 x 100 = 800%
Example