My suggestion is to start with an empty excel workbook. Then, for each month, you could issue code like this:

oExcel = Createobject("excel.application")
oWorkBook = oExcel.WorkBooks.Add

Then, for each month:

oWorkSheet = oWorkBook.WorkSheets.Add

So, if you have an existing workbook, you could do this:

oExcel = Createobject("excel.application")
oWorkbook = oExcel.Workbooks.Open("inventory.xls")

Once you have an object reference to a specific worksheet, you can use automation to populate the cells.

IMHO, this method will provide more granular control than the COPY TO command.

HTH...