vba - How to "flatten" or "collapse" a 2D Excel table into 1D?

Question

I have a two dimensional table with countries and years in Excel. eg.

        1961        1962        1963        1964
USA      a           x            g           y
France   u           e            h           a
Germany  o           x            n           p

I'd like to "flatten" it, such that I have Country in the first col, Year in the second col, and then value in the third col. eg.

Country      Year       Value
USA          1961       a
USA          1962       x
USA          1963       g
USA          1964       y
France       1961       u
              ...

The example I present here is only a 3x4 matrix, but the real dataset i have is significantly larger (roughly 50x40 or so).

Any suggestions how I can do this using Excel?

Answer 1

You can use the excel pivot table feature to reverse a pivot table (which is essentially what you have here):

Good instructions here:

http://spreadsheetpage.com/index.php/tip/creating_a_database_table_from_a_summary_table/

Which links to the following VBA code (put it in a module) if you don't want to follow the instructions by hand:

Sub ReversePivotTable()
'   Before running this, make sure you have a summary table with column headers.
'   The output table will have three columns.
    Dim SummaryTable As Range, OutputRange As Range
    Dim OutRow As Long
    Dim r As Long, c As Long

    On Error Resume Next
    Set SummaryTable = ActiveCell.CurrentRegion
    If SummaryTable.Count = 1 Or SummaryTable.Rows.Count < 3 Then
        MsgBox "Select a cell within the summary table.", vbCritical
        Exit Sub
    End If
    SummaryTable.Select
    Set OutputRange = Application.InputBox(prompt:="Select a cell for the 3-column output", Type:=8)
'   Convert the range
    OutRow = 2
    Application.ScreenUpdating = False
    OutputRange.Range("A1:C3") = Array("Column1", "Column2", "Column3")
    For r = 2 To SummaryTable.Rows.Count
        For c = 2 To SummaryTable.Columns.Count
            OutputRange.Cells(OutRow, 1) = SummaryTable.Cells(r, 1)
            OutputRange.Cells(OutRow, 2) = SummaryTable.Cells(1, c)
            OutputRange.Cells(OutRow, 3) = SummaryTable.Cells(r, c)
            OutputRange.Cells(OutRow, 3).NumberFormat = SummaryTable.Cells(r, c).NumberFormat
            OutRow = OutRow + 1
        Next c
    Next r
End Sub

-Adam