1233.33% is the change from 30 to 400
Calculation steps:
[( 400 - 30 ) ÷ 30] x 100 = 1233.33%
Formula
Percentage change = [(400 - 30) / 30] x 100
Subtract the new number by the original number
400 - 30 = 370
370 ÷ 30 = 12.333333333333334
12.333333333333334 x 100 = 1233.33%