-84.25% is the change from 819 to 129
Calculation steps:
[( 129 - 819 ) ÷ 819] x 100 = -84.25%
Formula
Percentage change = [(129 - 819) / 819] x 100
Subtract the new number by the original number
129 - 819 = -690
-690 ÷ 819 = -0.8424908424908425
-0.8424908424908425 x 100 = -84.25%