-81.63% is the change from 664 to 122
Calculation steps:
[( 122 - 664 ) ÷ 664] x 100 = -81.63%
Formula
Percentage change = [(122 - 664) / 664] x 100
Subtract the new number by the original number
122 - 664 = -542
-542 ÷ 664 = -0.8162650602409639
-0.8162650602409639 x 100 = -81.63%