-8.78% is the change from 991 to 904
Calculation steps:
[( 904 - 991 ) ÷ 991] x 100 = -8.78%
Formula
Percentage change = [(904 - 991) / 991] x 100
Subtract the new number by the original number
904 - 991 = -87
-87 ÷ 991 = -0.08779011099899092
-0.08779011099899092 x 100 = -8.78%