-13.44% is the change from 960 to 831
Calculation steps:
[( 831 - 960 ) ÷ 960] x 100 = -13.44%
Formula
Percentage change = [(831 - 960) / 960] x 100
Subtract the new number by the original number
831 - 960 = -129
-129 ÷ 960 = -0.134375
-0.134375 x 100 = -13.44%