Can someone please tell me what I am missing here.

I use the followig function to concatenate two columns of dates.

When I use the fill handle to autofill the function down the column, the
values calculated in the first cell of the column are carried down the
column -- without recalculating or updating for each individual iteration.

I cannot seem to force the function to recalcuate or examine each iteration
of the function independently?

Any help appreciated.
===================
Public Function OsteoDate(MyText) as String

Dim FromDate
FromDate = ActiveCell.Offset(0, 1).Text

Dim ToDate
ToDate = ActiveCell.Offset(0, 2).Text

If MyText = "" Then 'Check to see if first date column is null
OsteoDate = "on " & FromDate
Else 'concatenate both dates together with "from" and "to"
OsteoDate = "from " & FromDate & " to " & ToDate
End If

End Function