Here is my code, I cannot produce the output in the lstresults.Text box

Code:
Public Class Expense_Report
    Const expenseDivide As Double = 50
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
       
    End Sub
    Sub getResults()
        Dim fmtStr As String = "{0, -26}  {1, -10:C2}"
        Dim entertainment As Double = CType(txtEntertainment.Text, Double)
        Dim airline As Double = CType(txtPlaneFare.Text, Double)
        Dim lodging As Double = CType(txtLodging.Text, Double)
        Dim taxi As Double = CType(txtTaxi.Text, Double)

        Dim sum As Double = 0
        Dim fun As Double = 0
        Dim total As Double = 0

        With lstResults.Items
            sum = CType(txtPlaneFare.Text, Double) + CType(txtLodging.Text, Double) + CType(txtTaxi.Text, Double)
            fun = (entertainment * (expenseDivide / 100))
            total = sum + fun


            lstResults.Items.Clear()
            lstResults.Items.Add("Business Travel Expense")
            lstResults.Items.Add("")
            lstResults.Items.Add("Organization visited : ")
            lstResults.Items.Add(txtOrganization.Text)
            lstResults.Items.Add(txtDates.Text & " in " & txtLocation.Text)
            lstResults.Items.Add("")
            lstResults.Items.Add(String.Format(fmtStr, "Meals and entertainment", entertainment))
            lstResults.Items.Add(String.Format(fmtStr, "Airplane fare", airline))
            lstResults.Items.Add(String.Format(fmtStr, "Lodging", lodging))
            lstResults.Items.Add(String.Format(fmtStr, "Taxi fares", taxi))
            lstResults.Items.Add("")
            lstResults.Items.Add(String.Format(fmtStr, "Total other than meals and entertainment:", sum))
            lstResults.Items.Add(String.Format(fmtStr, "50% of meals and entertainment:", fun))

           
        End With

    End Sub
    
    
    

    

End Class