21.38% is the change from 421 to 511
Calculation steps:
[( 511 - 421 ) ÷ 421] x 100 = 21.38%
Formula
Percentage change = [(511 - 421) / 421] x 100
Subtract the new number by the original number
511 - 421 = 90
90 ÷ 421 = 0.21377672209026127
0.21377672209026127 x 100 = 21.38%