-97.69% is the change from 911 to 21
Calculation steps:
[( 21 - 911 ) ÷ 911] x 100 = -97.69%
Formula
Percentage change = [(21 - 911) / 911] x 100
Subtract the new number by the original number
21 - 911 = -890
-890 ÷ 911 = -0.9769484083424808
-0.9769484083424808 x 100 = -97.69%