-2.19% is the change from 960 to 939
Calculation steps:
[( 939 - 960 ) ÷ 960] x 100 = -2.19%
Formula
Percentage change = [(939 - 960) / 960] x 100
Subtract the new number by the original number
939 - 960 = -21
-21 ÷ 960 = -0.021875
-0.021875 x 100 = -2.19%