-29.39% is the change from 939 to 663
Calculation steps:
[( 663 - 939 ) ÷ 939] x 100 = -29.39%
Formula
Percentage change = [(663 - 939) / 939] x 100
Subtract the new number by the original number
663 - 939 = -276
-276 ÷ 939 = -0.2939297124600639
-0.2939297124600639 x 100 = -29.39%