-19.89% is the change from 900 to 721
Calculation steps:
[( 721 - 900 ) ÷ 900] x 100 = -19.89%
Formula
Percentage change = [(721 - 900) / 900] x 100
Subtract the new number by the original number
721 - 900 = -179
-179 ÷ 900 = -0.1988888888888889
-0.1988888888888889 x 100 = -19.89%