SUBTOTAL()-like UDF for rows with hidden columns

Intro

This is a follow-up to AVERAGE for unhidden columns...and SUM and COUNT

The code AVERAGE for unhidden columns...and SUM and COUNT provides a focused solution for someone who wants to be able to find the average of cells in a row, excluding those in hidden columns.  In a sense, all she wanted was the Worksheet function to work horizontally as well as vertically.  That's not unreasonable.  

Building on success

The one-function-at-a-time focused solution is the basis for a function that can be used for rows instead of columns.  All that was needed was a SELECT CASE ... END CASE.

• To be consistent, to uses the same inputs as the SUBTOTAL function, i.e. the Operation and the target ranges.
• The 1-11 operations values (1 for Average, etc) are omitted because I did not want to continue the confusion of the poorly described difference between the 1-11 range and the 1-111 range.  Hidden is Hidden, and my understanding of the 101-111 range is more in line with the behavior I think I see.  Either way, it would be simple to change back to the 1-11 range.

Function SubTotalColumns(Operation As Integer, ParamArray rngSource())

    Application.Volatile

    Dim rngCell As Range

    Dim rngVisible As Range

    Dim dblCtr As Double

    For dblCtr = LBound(rngSource) To UBound(rngSource)

        For Each rngCell In rngSource(dblCtr).Cells

            If Not rngCell.Columns(1).Hidden Then

                If rngVisible Is Nothing Then

                    Set rngVisible = rngCell

                Else

                    Set rngVisible = Union(rngVisible, rngCell)

                End If

            End If

        Next rngCell

    Next dblCtr

    Select Case Operation

        Case 101

            SubTotalColumns = Application.WorksheetFunction.Average(rngVisible)

        Case 102

            SubTotalColumns = Application.WorksheetFunction.count(rngVisible)

        Case 103

            SubTotalColumns = Application.WorksheetFunction.CountA(rngVisible)

        Case 104

            SubTotalColumns = Application.WorksheetFunction.max(rngVisible)

        Case 105

            SubTotalColumns = Application.WorksheetFunction.min(rngVisible)

        Case 106

            SubTotalColumns = Application.WorksheetFunction.Product(rngVisible)

        Case 107

            SubTotalColumns = Application.WorksheetFunction.StDev(rngVisible)

        Case 108

            SubTotalColumns = Application.WorksheetFunction.StDevP(rngVisible)

        Case 109

            SubTotalColumns = Application.WorksheetFunction.Sum(rngVisible)

        Case 110

            SubTotalColumns = Application.WorksheetFunction.var(rngVisible)

        Case 111

            SubTotalColumns = Application.WorksheetFunction.varP(rngVisible)

        End Select

End Function