-18.83% is the change from 818 to 664
Calculation steps:
[( 664 - 818 ) ÷ 818] x 100 = -18.83%
Formula
Percentage change = [(664 - 818) / 818] x 100
Subtract the new number by the original number
664 - 818 = -154
-154 ÷ 818 = -0.1882640586797066
-0.1882640586797066 x 100 = -18.83%