-5.25% is the change from 991 to 939
Calculation steps:
[( 939 - 991 ) ÷ 991] x 100 = -5.25%
Formula
Percentage change = [(939 - 991) / 991] x 100
Subtract the new number by the original number
939 - 991 = -52
-52 ÷ 991 = -0.05247225025227043
-0.05247225025227043 x 100 = -5.25%