-15.89% is the change from 988 to 831
Calculation steps:
[( 831 - 988 ) ÷ 988] x 100 = -15.89%
Formula
Percentage change = [(831 - 988) / 988] x 100
Subtract the new number by the original number
831 - 988 = -157
-157 ÷ 988 = -0.15890688259109312
-0.15890688259109312 x 100 = -15.89%