3650% is the change from 12 to 450
Calculation steps:
[( 450 - 12 ) ÷ 12] x 100 = 3650%
Formula
Percentage change = [(450 - 12) / 12] x 100
Subtract the new number by the original number
450 - 12 = 438
438 ÷ 12 = 36.5
36.5 x 100 = 3650%
Example