-81.66% is the change from 845 to 155
Calculation steps:
[( 155 - 845 ) ÷ 845] x 100 = -81.66%
Formula
Percentage change = [(155 - 845) / 845] x 100
Subtract the new number by the original number
155 - 845 = -690
-690 ÷ 845 = -0.8165680473372781
-0.8165680473372781 x 100 = -81.66%