3250% is the change from 12 to 402
Calculation steps:
[( 402 - 12 ) ÷ 12] x 100 = 3250%
Formula
Percentage change = [(402 - 12) / 12] x 100
Subtract the new number by the original number
402 - 12 = 390
390 ÷ 12 = 32.5
32.5 x 100 = 3250%
Example