20.8% is the change from 423 to 511
Calculation steps:
[( 511 - 423 ) ÷ 423] x 100 = 20.8%
Formula
Percentage change = [(511 - 423) / 423] x 100
Subtract the new number by the original number
511 - 423 = 88
88 ÷ 423 = 0.20803782505910165
0.20803782505910165 x 100 = 20.8%