5.15% is the change from 815 to 857
Calculation steps:
[( 857 - 815 ) ÷ 815] x 100 = 5.15%
Formula
Percentage change = [(857 - 815) / 815] x 100
Subtract the new number by the original number
857 - 815 = 42
42 ÷ 815 = 0.051533742331288344
0.051533742331288344 x 100 = 5.15%