Public Function CalcAPValue(targetDate As Date) As Double  ' edited
        Dim cumulativeAPValue As Double = 0
        Dim symbol As String
        Dim units As Double
        Dim posValue As Double

        For Each myRow As DataRow In myDataSet.Tables("AcquiredPositionsTbl").Rows
            symbol = myRow("Symbol").ToString().Trim
            units = myRow("Units")
            If symbol <> "CAccount" Then
                posValue = units * CalcMTM(symbol, targetDate)
                cumulativeAPValue = cumulativeAPValue + posValue
                myRow("Value") = posValue
            End If
        Next

        Return cumulativeAPValue
    End Function

Public Function CalcAPMargin(targetDate As Date) As Double
        Dim cumulativeAPMValue As Double = 0
        Dim symbol As String
        Dim units As Double
        Dim posValue As Double
        For Each myRow As DataRow In myDataSet.Tables("AcquiredPositionsTbl").Rows
            symbol = myRow("Symbol").ToString().Trim
            units = myRow("Units")
            If symbol <> "CAccount" And units < 0 Then
                posValue = units * CalcMTM(symbol, targetDate)
                cumulativeAPMValue = cumulativeAPMValue + posValue
            End If
        Next
        Return cumulativeAPMValue
    End Function