-11.37% is the change from 721 to 639
Calculation steps:
[( 639 - 721 ) ÷ 721] x 100 = -11.37%
Formula
Percentage change = [(639 - 721) / 721] x 100
Subtract the new number by the original number
639 - 721 = -82
-82 ÷ 721 = -0.11373092926490985
-0.11373092926490985 x 100 = -11.37%