52.49% is the change from 421 to 642
Calculation steps:
[( 642 - 421 ) ÷ 421] x 100 = 52.49%
Formula
Percentage change = [(642 - 421) / 421] x 100
Subtract the new number by the original number
642 - 421 = 221
221 ÷ 421 = 0.5249406175771971
0.5249406175771971 x 100 = 52.49%