Function TheorMWImpliedVol(Wgt As Object, SingleVols As Object, CorrMat As Object) As Double
    
    Dim n As Long, M As Long, i As Long, j As Long
    Dim Tmp As Double, SumKW As Double, KW As Double, SumTmp As Double
    Dim w() As Double
    Dim v() As Double
    
    n = Wgt.Columns.Count
    If Wgt.Rows.Count > n Then
        n = Wgt.Rows.Count
        ReDim w(1 To n)
        For i = 1 To n
            w(i) = Wgt(i, 1)
        Next i
    Else
        ReDim w(1 To n)
        For i = 1 To n
            w(i) = Wgt(1, i)
        Next i
    End If
    
    M = SingleVols.Columns.Count
    If SingleVols.Rows.Count > M Then
        M = SingleVols.Rows.Count
        ReDim v(1 To n)
        For i = 1 To n
            v(i) = SingleVols(i, 1)
        Next i
    Else
        ReDim v(1 To n)
        For i = 1 To n
            v(i) = SingleVols(1, i)
        Next i
    End If
    
    If M <> n Then
        TheorMWImpliedVol = -100
        Exit Function
    End If
      
    For i = 1 To n
        Tmp = w(i) ^ 2 * v(i) ^ 2
        SumTmp = SumTmp + Tmp
        For j = i + 1 To M
            KW = w(i) * w(j) * v(i) * v(j) * CorrMat(i, j)
            SumKW = SumKW + KW
        Next j
    Next i
    
    TheorMWImpliedVol = (SumTmp + SumKW) ^ 0.5
    
End Function