Best way to do Version Control for MS Excel

Sub SaveCodeModules()

'This code Exports all VBA modules
Dim i%, sName$

With ThisWorkbook.VBProject
    For i% = 1 To .VBComponents.Count
        If .VBComponents(i%).CodeModule.CountOfLines > 0 Then
            sName$ = .VBComponents(i%).CodeModule.Name
            .VBComponents(i%).Export "X:ToolsMyExcelMacros" & sName$ & ".vba"
        End If
    Next i
End With

End Sub

Sub ImportCodeModules()

With ThisWorkbook.VBProject
    For i% = 1 To .VBComponents.Count

        ModuleName = .VBComponents(i%).CodeModule.Name

        If ModuleName <> "VersionControl" Then
            If Right(ModuleName, 6) = "Macros" Then
                .VBComponents.Remove .VBComponents(ModuleName)
                .VBComponents.Import "X:DataMySheet" & ModuleName & ".vba"
           End If
        End If
    Next i
End With

End Sub

Private Sub Workbook_Open()

ImportCodeModules

End Sub

Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)

SaveCodeModules

End Sub

'This code Exports all VBA modules
Dim i%, sName$

With ThisWorkbook.VBProject
    For i% = 1 To .VBComponents.Count
        If .VBComponents(i%).CodeModule.CountOfLines > 0 Then
            sName$ = .VBComponents(i%).CodeModule.Name
            .VBComponents(i%).Export "C:Code" & sName$ & ".vba"
        End If
    Next i
End With