Hi Kameel
Its possible only.

Example:
First Row months (A1: Jan, B1: Feb,…..)
Second Row values (A2: 10, B2: 20,…..)
Put any column (eg. K10) this function:
=ADDRESS(1,COUNTA(A1:AA1)-3)&":"&ADDRESS(2,COUNTA(A1:AA1))
You will get the cell address of new four months.
Click Insert–>Name–>Define
Enter “CName” in ‘Names in workbook’ field
Refers to area: =INDIRECT(Sheet1!$K$10)
Then click OK.
Open Visual Basic Editor (Alt+F11)
Go particular sheet object area
Paste below mentioned code

‘VB Code
Dim tmpBC As String
Private Sub Worksheet_Activate()
   tmpBC = Range("K10").Value
End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
   If tmpBC <> Range("K10").Value Then
       Call Refesh_Chart
   End If
End Sub

Private Sub Refesh_Chart()
Application.ScreenUpdating = False
   ActiveSheet.ChartObjects("Chart 4").Activate 'put your chart name
   ActiveChart.ChartArea.Select
   Dim rng As Range
   Set rng = Range("Cname")
       ActiveChart.SetSourceData Source:=rng, PlotBy:= _
       xlRows
       Range("A1").Select
Application.ScreenUpdating = True
End Sub

If you are not able to understand please mail to mohdraf@hotmail.com with
sample file

Thanks and regards
Muhammed Rafeek M

See
Dynamic Charts
http://www.tushar-mehta.com/excel/newsgroups/dynamic_charts/index.html
particularly, example 2.