-79.1% is the change from 818 to 171
Calculation steps:
[( 171 - 818 ) ÷ 818] x 100 = -79.1%
Formula
Percentage change = [(171 - 818) / 818] x 100
Subtract the new number by the original number
171 - 818 = -647
-647 ÷ 818 = -0.7909535452322738
-0.7909535452322738 x 100 = -79.1%