220% is the change from 100 to 320
Calculation steps:
[( 320 - 100 ) ÷ 100] x 100 = 220%
Formula
Percentage change = [(320 - 100) / 100] x 100
Subtract the new number by the original number
320 - 100 = 220
220 ÷ 100 = 2.2
2.2 x 100 = 220%
Example