-8.28% is the change from 664 to 609
Calculation steps:
[( 609 - 664 ) ÷ 664] x 100 = -8.28%
Formula
Percentage change = [(609 - 664) / 664] x 100
Subtract the new number by the original number
609 - 664 = -55
-55 ÷ 664 = -0.08283132530120482
-0.08283132530120482 x 100 = -8.28%