40.38% is the change from 421 to 591
Calculation steps:
[( 591 - 421 ) ÷ 421] x 100 = 40.38%
Formula
Percentage change = [(591 - 421) / 421] x 100
Subtract the new number by the original number
591 - 421 = 170
170 ÷ 421 = 0.40380047505938244
0.40380047505938244 x 100 = 40.38%