Private Sub Worksheet_Change(ByVal Target As Range)
    If Not Intersect(Target, Range("C15")) Is Nothing Then
        Application.EnableEvents = False
Dim iMonth As String
Dim FoundMonth As Range
Dim j As Integer
Dim iSumma As Double
        iMonth = Target.Text
        Range("C17") = 0
      Set FoundMonth = Rows(3).Find(iMonth, , xlValues, xlWhole)
      For j = 3 To FoundMonth.Column
        If Not Cells(3, j) Like "*квартал" Then
          iSumma = iSumma + Cells(4, j)
        End If
      Next
      Range("C17") = iSumma                  'для наименования 1
      Range("C17").NumberFormat = "#,##0"
    End If
    Application.EnableEvents = True
End Sub