Loop through a subset of worksheets will not work

Greetings,

I'm trying to insert two rows in a subset of worksheets in a workbook by defining a range in a worksheet and loop through the worksheets in that range, but the code will only run on the active worksheet.

    Sub StatePIPData()
    Dim sheet_name As Range
    For Each sheet_name In Sheets("WS").Range("A:A")
        If sheet_name.Value = "" Then
            Exit For
        Else
             'Insert 2 rows for 2011 and 2012's data
             Range("A14").EntireRow.Insert
             Cells(14, 1) = Cells(15, 1) + 1
             Range("A14").EntireRow.Insert
             Cells(14, 1) = Cells(15, 1) + 1
             End If
        Next sheet_name
     End Sub

Any thoughts on how I could get this loop to work?

Thank you very much,