-4.09% is the change from 979 to 939
Calculation steps:
[( 939 - 979 ) ÷ 979] x 100 = -4.09%
Formula
Percentage change = [(939 - 979) / 979] x 100
Subtract the new number by the original number
939 - 979 = -40
-40 ÷ 979 = -0.04085801838610827
-0.04085801838610827 x 100 = -4.09%