Hello all,

I use a function that returns an union of all visible cells:

Function Vis(Rin As Range) As Range
'Returns the subset of Rin that is visible
Dim cell As Range
Application.Volatile
Set Vis = Nothing
For Each cell In Rin
If Not (cell.EntireRow.Hidden Or cell.EntireColumn.Hidden) Then
If Vis Is Nothing Then
Set Vis = cell
Else
Set Vis = Union(Vis, cell)
End If
End If
Next cell
End Function

The function above works well and I can use it for example to
calculate the sum with '=SUM(Vis(A1:A9))'.
But some functions do not work, for example '=CORREL(Vis(A1:A9),Vis
(B1:B9))' give me a '#VALUE!' if the union is a union of more than one
range. How can I calculate the correlation?