Dynamic generation of "progress bars"

[me]

Hello List,
Please help point me in the right direction once again?  What I'm
attempting to achieve is something like:

(<div> "progress"
                  (<div> '("progress-bar progress-bar-success"
                           (role . "progressbar")
                           (aria-valuenow . "-79")
                           (aria-valuemin . "-100")
                           (aria-valuemax . "100")
                           (style . "width: 79%") )
                     (<span> "sr-only" "79% Nominal") ) )


What I have is:

(de make-progress-bar (bar-type width)
   (<div> "progress"
      (<div> '(`(,pack "progress-bar progess-bar-" ,bar-type)
               (role . "progressbar")
               (aria-valuenow . `(,pack ,width))
               (aria-valuemin . "-100")
               (aria-valuemax . "100")
               (style . `(,pack "width: " ,width "%")) )
         (<span> "sr-only" `(,pack ,width "% Nominal")) ) ) )


What is the idiomatic way to manipulate text such that I can dynamically
generate different types of progress bars?  The idea being that I could use
different color coded static progress bars as a simple form of charting
data.

Thank you.