2122.22% is the change from 18 to 400
Calculation steps:
[( 400 - 18 ) ÷ 18] x 100 = 2122.22%
Formula
Percentage change = [(400 - 18) / 18] x 100
Subtract the new number by the original number
400 - 18 = 382
382 ÷ 18 = 21.22222222222222
21.22222222222222 x 100 = 2122.22%