Searched the web for two hours to not discover a built-in Excel 2007 formula to count only bolded rows.
This report is generated from MSAccess. Primary rows are bold, duplicate rows are not.
A2 has the text for a sumproducts count - with filters only the visible rows are counted.

If the Active Filter shown in the attachment is used to hide the non-bold - the formula works OK.

So,, it looks as if a UDF (User Defined Function) is required.
If a UDF is created, will my users get that pesky "this is not a macro free worksheet" message?

Or .... if you notice Column G is hidden.
Would it be better to put a AG hidden column at the end - and have a True / False that represents the bolded row? Then I could just simply adjust the formula:
=SUMPRODUCT(SUBTOTAL(3, OFFSET(C6:C589, ROW(C6:C589)-ROW(C6),0,1)),--(C6:C589=A2))
to check for both Row C AND a True in row AG


FYI Application.Volatile i- forces update when some othe event fires
Count only bold cells with a specific value.gif