Dim dt As New DataTable
      dt.Columns.Add("Date")
      dt.Columns.Add("Gross Sales")

      Dim Folder As New IO.DirectoryInfo("c:test")
      Dim lstLines As New List(Of String)


For Each fileentries As String In Folder.GetFiles("s*",   IO.SearchOption.AllDirectories).OrderByDescending(Function(x) x.Name).Select(Function(x) x.FullName)
    lstLines.AddRange(File.ReadAllLines(fileentries))
Next


      Dim i As Integer
      Dim OuterLoopIterations As Integer = CInt(lstLines.Count / 22)
      For iterations = 0 To OuterLoopIterations - 1
          Dim row = dt.NewRow
          For col = 0 To 21
              row(col) = lstLines(i).Remove(0, 2) 'i have removed the first 2 characters of each string

              i += 1
          Next
          dt.Rows.Add(row(2), row(5), row(12), row(13), row(14), row(15),  row(7), row(8), row(11))

      Next

DataGridView1.DataSource = dt
'the code i tried applying
DataGridView1.Columns("Gross Sales").DefaultCellStyle.Format = "##,0"