-15.18% is the change from 909 to 771
Calculation steps:
[( 771 - 909 ) ÷ 909] x 100 = -15.18%
Formula
Percentage change = [(771 - 909) / 909] x 100
Subtract the new number by the original number
771 - 909 = -138
-138 ÷ 909 = -0.15181518151815182
-0.15181518151815182 x 100 = -15.18%