-97.29% is the change from 664 to 18
Calculation steps:
[( 18 - 664 ) ÷ 664] x 100 = -97.29%
Formula
Percentage change = [(18 - 664) / 664] x 100
Subtract the new number by the original number
18 - 664 = -646
-646 ÷ 664 = -0.9728915662650602
-0.9728915662650602 x 100 = -97.29%