and a tweak to plot and export multiple charts from Worksheet "min max & march of khamir"
Code:
Sub blah()
With ThisWorkbook.Worksheets("min max & march of khamir")
  For i = 1 To 61 Step 2
    lr = .Cells(Rows.Count, i + 1).End(xlUp).Row
    .ChartObjects("Chart 2").Chart.SetSourceData Source:=.Range(.Cells(1, i), .Cells(lr, i + 1))
    .ChartObjects("Chart 2").Chart.Export ThisWorkbook.Path & Application.PathSeparator & "Chart " & Format(i, "00") & " " & Format(Now, "DD-MM-YY_HH.MM.SS_AM/PM") & ".PNG"
  Next i
End With
End Sub