Can I access the speed limit from an IQ App?

THis is possibly a dumb question, I am really just finding my feet in this.  I have however spent quite a while searching the documentation and while I have found out how I can access many bits of information, I have not worked out whether I can use the 'Speed Limit' field in an App.

I basically want to create an app that turns my GPSMAP 66 into a large, horizontal speedo with a speed limit display/change of colour.  Is the speed limit not available in the current SDK because I can't find it!?

Appreciate any help/confirmation.

Ta

dazey