-90.21% is the change from 991 to 97
Calculation steps:
[( 97 - 991 ) ÷ 991] x 100 = -90.21%
Formula
Percentage change = [(97 - 991) / 991] x 100
Subtract the new number by the original number
97 - 991 = -894
-894 ÷ 991 = -0.9021190716448032
-0.9021190716448032 x 100 = -90.21%