30.81% is the change from 620 to 811
Calculation steps:
[( 811 - 620 ) ÷ 620] x 100 = 30.81%
Formula
Percentage change = [(811 - 620) / 620] x 100
Subtract the new number by the original number
811 - 620 = 191
191 ÷ 620 = 0.30806451612903224
0.30806451612903224 x 100 = 30.81%