-81.33% is the change from 664 to 124
Calculation steps:
[( 124 - 664 ) ÷ 664] x 100 = -81.33%
Formula
Percentage change = [(124 - 664) / 664] x 100
Subtract the new number by the original number
124 - 664 = -540
-540 ÷ 664 = -0.8132530120481928
-0.8132530120481928 x 100 = -81.33%