-84.37% is the change from 819 to 128
Calculation steps:
[( 128 - 819 ) ÷ 819] x 100 = -84.37%
Formula
Percentage change = [(128 - 819) / 819] x 100
Subtract the new number by the original number
128 - 819 = -691
-691 ÷ 819 = -0.8437118437118437
-0.8437118437118437 x 100 = -84.37%