If then else statement

What I am trying to accomplish is to have a SQL select statement look in a tbl and pull out pay information for an individual.  But my problem lies in this the pay tables only go to certian yrs so that an E4-6 makes no more than an E4-8.  So the cut of would be an person with rank E-4 and over 6 years makes this scale.  so on for rest of the pay scale as well.  Here is my code so far.

I select the GRYRs from an existing label that is populated with a persons info.  I then do an sql statemnt to look up the scale such as E5-6, E4-6 so on.  Then depending on what comes back it does the calcs.  But my problem is above it returns nothing if there is an E4-8 because on the pay scale it does not exist for anything over adn E4-6 because they max out at 6 years.

 Private Sub Calc()
        Dim GrYrs As String = lblPayGrYrs.Text

        sql = "select strBase, strQtrs, strRats, strMisc, strFDWH from MNSadPaytables.dbo.tblMnSadDutyPay Where strGrdYrs = '" & GrYrs & "'"

        myDataTable = New DataTable
        myDataTable = getData(sql)

        lblstrbase.Text = myDataTable.Rows(0)(0)
        lblstrqtrs.Text = myDataTable.Rows(0)(1)
        lblstrRats.Text = myDataTable.Rows(0)(2)
        lblstrmisc.Text = myDataTable.Rows(0)(3)
        lblstrFWTH.Text = myDataTable.Rows(0)(4)

        Dim Days As String = lblDutyDays.Text
        Dim base As Decimal = lblstrbase.Text
        Dim Diff As Decimal = lblstrmisc.Text
        Dim Qtrs As Decimal = lblstrqtrs.Text
        Dim Rats As Decimal = lblstrRats.Text
        Dim FedT As Decimal = lblstrFWTH.Text
        Dim total As Decimal
        Dim Grand As Decimal
        Dim TaxTotal As Decimal
        Dim TotalCheck As Decimal

        total = base + Qtrs + Rats
        TaxTotal = FedT * Days

        If total < 130.0 Then
            Grand = (total + Diff) * Days
        Else
            Grand = total * Days
        End If

        TotalCheck = Grand - TaxTotal

        lblTotalEntitlement.Text = Grand.ToString("c")
        lblBasePay.Text = base.ToString("c")
        lblDiffPay.Text = Diff.ToString("c")
        lblHouseAllow.Text = Qtrs.ToString("c")
        lblRations.Text = Rats.ToString("c")
        lblFTWH.Text = FedT.ToString("c")
        lblTotalWH.Text = TaxTotal.ToString("c")
        lblTotalCheck.Text = TotalCheck.ToString("c")
    End Sub

End Class