15.21% is the change from 815 to 939
Calculation steps:
[( 939 - 815 ) ÷ 815] x 100 = 15.21%
Formula
Percentage change = [(939 - 815) / 815] x 100
Subtract the new number by the original number
939 - 815 = 124
124 ÷ 815 = 0.1521472392638037
0.1521472392638037 x 100 = 15.21%