1550% is the change from 20 to 330
Calculation steps:
[( 330 - 20 ) ÷ 20] x 100 = 1550%
Formula
Percentage change = [(330 - 20) / 20] x 100
Subtract the new number by the original number
330 - 20 = 310
310 ÷ 20 = 15.5
15.5 x 100 = 1550%
Example