Delete blank cells in a column - excel

Question

The following code converts a table of values to a single column.
The problem is, with my table the number of rows in each column decreases by one for each successive column. Similar to the table shown below.
I am VERY new to writing code and only know the very basics. I copied a script found online to convert a range of values to a single column. The portion of code that I wrote to delete any blank cells is slowing the code tremendously. To convert around 250,000 points to a column is taking roughly 9 hours. I am hoping to reduce the processing time as this is a script I expect to use regularly.
Sub CombineColumns()
Application.ScreenUpdating = False
Application.EnableEvents = False
Dim rng As Range
Dim iCol As Long
Dim lastCell As Long
Dim K As Long
K = 484
'set K equal to the number of data points that created the range
Set rng = ActiveCell.CurrentRegion
lastCell = rng.Columns(1).Rows.count + 1
For iCol = 2 To rng.Columns.count
Range(Cells(1, iCol), Cells(rng.Columns(iCol).Rows.count, iCol)).Cut
ActiveSheet.Paste Destination:=Cells(lastCell, 1)
lastCell = lastCell + rng.Columns(iCol).Rows.count
Next iCol
Dim z As Long
Dim m As Long
z = K ^ 2
For Row = z To 1 Step -1
If Cells(Row, 1) = 0 Then
Range("A" & Row).Delete Shift:=xlUp
Application.StatusBar = "Progress: " & Row & " of z: " & Format((z - Row) / z, "Percent")
DoEvents
End If
Next
Application.StatusBar = False
Application.ScreenUpdating = True
Application.EnableEvents = True
End Sub
Sample Table Structure

Answer 1

Because I gave errant information on where this should be posted.
The following code will do what you want nearly instantly.
I used arrays to limit the number of interactions with the worksheet.
Sub foo5()
Dim ws As Worksheet
Dim rng() As Variant
Dim oarr() As Variant
Dim i&, j&, k&
Set ws = ThisWorkbook.Worksheets("Sheet19") 'Change to your sheet
With ws
rng = .Range("A1", .Cells(.Cells(.Rows.Count, 1).End(xlUp).Row, .Cells(1, .Columns.Count).End(xlToLeft))).Value
ReDim oarr(1 To Application.WorksheetFunction.CountA(rng), 1 To 1)
k = 1
For i = LBound(rng, 1) To UBound(rng, 1)
For j = LBound(rng, 2) To UBound(rng, 2)
If rng(i, j) <> "" Then
oarr(k, 1) = rng(i, j)
k = k + 1
End If
Next j
Next i
.Range("A1", .Cells(.Cells(.Rows.Count, 1).End(xlUp).Row, .Cells(1, .Columns.Count).End(xlToLeft))).Clear
.Range("A1").Resize(UBound(oarr), 1).Value = oarr
End With
End Sub