23.12% is the change from 666 to 820
Calculation steps:
[( 820 - 666 ) ÷ 666] x 100 = 23.12%
Formula
Percentage change = [(820 - 666) / 666] x 100
Subtract the new number by the original number
820 - 666 = 154
154 ÷ 666 = 0.23123123123123124
0.23123123123123124 x 100 = 23.12%