8.58% is the change from 664 to 721
Calculation steps:
[( 721 - 664 ) ÷ 664] x 100 = 8.58%
Formula
Percentage change = [(721 - 664) / 664] x 100
Subtract the new number by the original number
721 - 664 = 57
57 ÷ 664 = 0.0858433734939759
0.0858433734939759 x 100 = 8.58%