1400% is the change from 30 to 450
Calculation steps:
[( 450 - 30 ) ÷ 30] x 100 = 1400%
Formula
Percentage change = [(450 - 30) / 30] x 100
Subtract the new number by the original number
450 - 30 = 420
420 ÷ 30 = 14
14 x 100 = 1400%
Example