-81.19% is the change from 909 to 171
Calculation steps:
[( 171 - 909 ) ÷ 909] x 100 = -81.19%
Formula
Percentage change = [(171 - 909) / 909] x 100
Subtract the new number by the original number
171 - 909 = -738
-738 ÷ 909 = -0.8118811881188119
-0.8118811881188119 x 100 = -81.19%