Percentage Calculation on Staus Bar Graphs

I was wondering if the bar graph percentage calculation from the V=/ calculation is available as a code?

I want to create a status bar graph showing how much space the selected files would take up if they were written to a DVD. However I want to use the F=3 parameter to fill the section with the bar graph and supply my own text over the top including the percentage. Something like this:

{bg+F=3,T=n,V={sb}/4.7GB,C3=#ff0000}{xxx}% of DVD Filled

where {xxx} is the code showing the percentage that would otherwise be displayed without the T=n parameter.

Reason for this is that the percentage displayed by default when using V=/ is overlayed on top of any text additional text I supply. T=n gets rid of the overlayed percentage but I still want this information to display alongside my text.