-13.13% is the change from 830 to 721
Calculation steps:
[( 721 - 830 ) ÷ 830] x 100 = -13.13%
Formula
Percentage change = [(721 - 830) / 830] x 100
Subtract the new number by the original number
721 - 830 = -109
-109 ÷ 830 = -0.13132530120481928
-0.13132530120481928 x 100 = -13.13%