Need help with variable

I'm having trouble figuring out why the code below won't work.  It works when I put it within a subroutine, but I need it to be accessible to any and every sub or function in my partial class so I put it right below the partial class statement.  But I get a "declaration expected" error on amnsmgr.
Am I doing something wrong?
 Partial Class importXml Inherits System.Web.UI.Page Private amnsmgr As XmlNamespaceManager = New XmlNamespaceManager(AMnav.NameTable) amnsmgr.AddNamespace("am", "http://ns.super.org/xml/v1/") Thanks! ...