310.5% is the change from 200 to 821
Calculation steps:
[( 821 - 200 ) ÷ 200] x 100 = 310.5%
Formula
Percentage change = [(821 - 200) / 200] x 100
Subtract the new number by the original number
821 - 200 = 621
621 ÷ 200 = 3.105
3.105 x 100 = 310.5%
Example