-77.9% is the change from 819 to 181
Calculation steps:
[( 181 - 819 ) ÷ 819] x 100 = -77.9%
Formula
Percentage change = [(181 - 819) / 819] x 100
Subtract the new number by the original number
181 - 819 = -638
-638 ÷ 819 = -0.778998778998779
-0.778998778998779 x 100 = -77.9%