30.87% is the change from 635 to 831
Calculation steps:
[( 831 - 635 ) ÷ 635] x 100 = 30.87%
Formula
Percentage change = [(831 - 635) / 635] x 100
Subtract the new number by the original number
831 - 635 = 196
196 ÷ 635 = 0.30866141732283464
0.30866141732283464 x 100 = 30.87%