-81.53% is the change from 850 to 157
Calculation steps:
[( 157 - 850 ) ÷ 850] x 100 = -81.53%
Formula
Percentage change = [(157 - 850) / 850] x 100
Subtract the new number by the original number
157 - 850 = -693
-693 ÷ 850 = -0.8152941176470588
-0.8152941176470588 x 100 = -81.53%