-3.19% is the change from 939 to 909
Calculation steps:
[( 909 - 939 ) ÷ 939] x 100 = -3.19%
Formula
Percentage change = [(909 - 939) / 939] x 100
Subtract the new number by the original number
909 - 939 = -30
-30 ÷ 939 = -0.03194888178913738
-0.03194888178913738 x 100 = -3.19%