Problem with the Static Datatable? any help asap pls?

Question

Hi,

    In my application i have few datatables. but one of the datatable is getting cleared when the page postbacks. Sometimes it works fine. sometimes i am facing this issue. Can anybody help me out pls.

Code Snippet:

  public static DataTable dtAnswer = new DataTable();

    public static DataTable dtPartitioned = new DataTable();

    public static DataTable dtAnsCount;

getting an  error at this point,

   if (dtAnsCount.Columns.Count == 0)

        {

}

Note:[The error is occuring at certain instance - saying object reference not set to an instance, which says that datatable doesn't exists]

Thanks in Advance!

Regards,

Divya