String Values getting reset in VB.Net on ASP.Net 2.0 page

Partial Class Default2
    Inherits System.Web.UI.Page
    Dim holidays(12, 31) As String
 
    Sub Calendar1_DayRender(ByVal sender As Object, ByVal e As DayRenderEventArgs)
        Dim d As CalendarDay
        Dim c As TableCell
 
        d = e.Day
        c = e.Cell
 
        If d.IsOtherMonth Then
            c.Controls.Clear()
        Else
            Try
                Dim Hol As String
                Hol = holidays(d.Date.Month, d.Date.Day)
 
                If Hol <> "" Then
                    c.Controls.Add(New LiteralControl("<br>" + Hol))
                End If
            Catch exc As Exception
                Response.Write(exc.ToString())
            End Try
        End If
    End Sub
 
    Sub Date_Selected(ByVal sender As Object, ByVal e As EventArgs) Handles Calendar1.SelectionChanged
        If pnlCustomEntry.Visible = False Then
            pnlCustomEntry.Visible = True
        End If
        Label1.Text = "Selected date is: " + Calendar1.SelectedDate.ToShortDateString
        Label2.Text = Calendar1.SelectedDate.ToShortDateString
        Label3.Text = holidays(Calendar1.SelectedDate.Date.Month, Calendar1.SelectedDate.Date.Day)
    End Sub
 
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Dim temp As Object = "New Year's Day"
        holidays(1, 1) = temp
        holidays(1, 26) = "Australia Day"
        holidays(2, 2) = "Groundhog Day"
        holidays(2, 14) = "Valentine's Day"
        holidays(3, 17) = "St. Patrick's Day"
        holidays(4, 1) = "April Fool's Day"
        holidays(5, 1) = "May Day"
        holidays(6, 15) = "My Birthday"
        holidays(7, 15) = "My Anniversary"
        holidays(8, 15) = "My Mother's Birthday"
        holidays(9, 24) = "Autumnal Equinox"
        holidays(12, 26) = "Boxing Day"
        ' this line sets the calendar to start on January of next year
        Calendar1.VisibleDate = New Date(Now.Year + 1, 1, 1)
    End Sub
 
    Protected Sub Calendar1_VisibleMonthChanged(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.MonthChangedEventArgs) Handles Calendar1.VisibleMonthChanged
        pnlCustomEntry.Visible = False
        'This portion keeps the calendar restricted to next year
        If Calendar1.VisibleDate.Year = Now.Year Then
            Calendar1.VisibleDate = New Date(Now.Year + 1, Calendar1.VisibleDate.Month, Calendar1.VisibleDate.Day)
        End If
    End Sub
 
    Protected Sub butCustomAddEntry_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles butAddCustomEntry.Click
        holidays(Calendar1.SelectedDate.Date.Month, Calendar1.SelectedDate.Date.Day) = txtCustomEntry.Text()
    End Sub
End Class