15.78% is the change from 450 to 521
Calculation steps:
[( 521 - 450 ) ÷ 450] x 100 = 15.78%
Formula
Percentage change = [(521 - 450) / 450] x 100
Subtract the new number by the original number
521 - 450 = 71
71 ÷ 450 = 0.15777777777777777
0.15777777777777777 x 100 = 15.78%