-18.34% is the change from 818 to 668
Calculation steps:
[( 668 - 818 ) ÷ 818] x 100 = -18.34%
Formula
Percentage change = [(668 - 818) / 818] x 100
Subtract the new number by the original number
668 - 818 = -150
-150 ÷ 818 = -0.18337408312958436
-0.18337408312958436 x 100 = -18.34%