You will need the correct formula! Set it up as a function CCfn(SPAN):= ....whatever the formula is.
Then use a vector of values of SPAN, say:
i = 0..100 (index counter)
Span[i:= i*5/100
CC[i:= CCfn(Span[i)
Then just plot CC vs Span.
(NB The [ gives you a true subscript in Mathcad)
The first essential is to get the correct formula!! When you get this, if you post it here, someone will undoubtedly plot it for you if that's the part that is causing difficulty.
Alan