DropDownList sort by Desc

My DropDown List is 

<asp:DropDownList ID="drplist" runat="server" > <asp:ListItem>1</asp:ListItem> <asp:ListItem>2</asp:ListItem> <asp:ListItem>3</asp:ListItem> <asp:ListItem>4</asp:ListItem> </asp:DropDownList>

It display 1,2,3,4 in User interface

Now I like to see result in reversing order like 4,3,2,1 

What i need to write ?
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