13.5% is the change from 600 to 681
Calculation steps:
[( 681 - 600 ) ÷ 600] x 100 = 13.5%
Formula
Percentage change = [(681 - 600) / 600] x 100
Subtract the new number by the original number
681 - 600 = 81
81 ÷ 600 = 0.135
0.135 x 100 = 13.5%
Example