-79.22% is the change from 664 to 138
Calculation steps:
[( 138 - 664 ) ÷ 664] x 100 = -79.22%
Formula
Percentage change = [(138 - 664) / 664] x 100
Subtract the new number by the original number
138 - 664 = -526
-526 ÷ 664 = -0.7921686746987951
-0.7921686746987951 x 100 = -79.22%