2400% is the change from 18 to 450
Calculation steps:
[( 450 - 18 ) ÷ 18] x 100 = 2400%
Formula
Percentage change = [(450 - 18) / 18] x 100
Subtract the new number by the original number
450 - 18 = 432
432 ÷ 18 = 24
24 x 100 = 2400%
Example