-9.88% is the change from 911 to 821
Calculation steps:
[( 821 - 911 ) ÷ 911] x 100 = -9.88%
Formula
Percentage change = [(821 - 911) / 911] x 100
Subtract the new number by the original number
821 - 911 = -90
-90 ÷ 911 = -0.09879253567508232
-0.09879253567508232 x 100 = -9.88%