-97.78% is the change from 900 to 20
Calculation steps:
[( 20 - 900 ) ÷ 900] x 100 = -97.78%
Formula
Percentage change = [(20 - 900) / 900] x 100
Subtract the new number by the original number
20 - 900 = -880
-880 ÷ 900 = -0.9777777777777777
-0.9777777777777777 x 100 = -97.78%