Public Sub MergeAggregate()
Const FOLDER_PATH = "C:\Users\maggo\Desktop\Auswertung Dez 2019\C21\Ausgehend\"
Dim strFilename As String
Dim objTargetWorksheet As Worksheet
Dim objSourceWorkbook As Workbook
Application.ScreenUpdating = False
Set objTargetWorksheet = ActiveSheet
strFilename = Dir$(FOLDER_PATH & "*.xls")
Do Until strFilename = vbNullString
Set objSourceWorkbook = Workbooks.Open(Filename:=FOLDER_PATH & strFilename)
With objSourceWorkbook.ActiveSheet
.Range(.Cells(2, 1), .Cells(.Cells(.Rows.count, 1).End(xlUp).Row, 15)).Copy
End With
With objTargetWorksheet
.Paste Destination:=.Cells(.Rows.count, 1).End(xlUp).Offset(1, 0)
End With
Application.CutCopyMode = False
Call objSourceWorkbook.Close(SaveChanges:=False)
strFilename = Dir$()
Set objSourceWorkbook = Nothing
Loop
Set objTargetWorksheet = Nothing
Application.ScreenUpdating = True
End Sub