300% is the change from 200 to 800
Calculation steps:
[( 800 - 200 ) ÷ 200] x 100 = 300%
Formula
Percentage change = [(800 - 200) / 200] x 100
Subtract the new number by the original number
800 - 200 = 600
600 ÷ 200 = 3
3 x 100 = 300%
Example