397.5% is the change from 80 to 398
Calculation steps:
[( 398 - 80 ) ÷ 80] x 100 = 397.5%
Formula
Percentage change = [(398 - 80) / 80] x 100
Subtract the new number by the original number
398 - 80 = 318
318 ÷ 80 = 3.975
3.975 x 100 = 397.5%
Example