-21.37% is the change from 917 to 721
Calculation steps:
[( 721 - 917 ) ÷ 917] x 100 = -21.37%
Formula
Percentage change = [(721 - 917) / 917] x 100
Subtract the new number by the original number
721 - 917 = -196
-196 ÷ 917 = -0.21374045801526717
-0.21374045801526717 x 100 = -21.37%