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                                                                    EXHIBIT 10.1


                              TAX SHARING AGREEMENT

      THIS TAX SHARING AGREEMENT ("Agreement") is made as of August 31, 1999 by
and among Washington Mutual, Inc., a Washington corporation ("WMI"), Washington
Mutual Bank fsb, a federal savings bank ("WMBfsb"), Washington Mutual Bank, a
state chartered savings bank ("WMB"), New American Capital, Inc., a savings and
loan holding company whose principle subsidiary is Washington Mutual Bank, FA, a
federal savings association ("WMBFA") and Aristar, Inc., a Delaware corporation,
on behalf of themselves, each of their current subsidiaries and all subsidiaries
that any one or more of them may own in the future (together, the
"Subsidiaries"). This agreement supersedes the Tax Sharing Agreement dated March
30, 1998 among WMI and subsidiaries.

      WHEREAS, WMI owns 100% of the issued and outstanding capital stock of
WMBfsb, WMB and NACI.

      WHEREAS, WMI owns either directly or indirectly, 100% of the issued and
outstanding capital stock of the Subsidiaries;

      WHEREAS, NACI owns 100% of the issued and outstanding capital stock of
WMBFA and Aristar, Inc.;

      WHEREAS, WMI, WMBfsb, WMB, NACI, WMBFA, Aristar, Inc., and the
Subsidiaries join in the filing of a consolidated federal income tax return
and combined or consolidated tax returns in various states and other local
taxing jurisdictions; and

      WHEREAS, it is the desire of the parties hereto to enter into a definitive
written Tax Sharing Agreement, which agreement describes the manner in which the
consolidated federal income tax liability is shared among the members of the
consolidated group and the manner in which the combined or consolidated state or
other local tax is shared among members of the combined or consolidated group;

      NOW, THEREFORE, in consideration of the foregoing premises, the parties
agree as follows:

1.    For all taxable years during which WMBfsb, WMB, NACI, WMBFA, Aristar,
      Inc., or any Subsidiary is a member of an "affiliated group" of WMI as
      defined in Section 1504 of the Internal Revenue Code and is required to
      join in the filing of a consolidated federal income tax return of WMI and
      its consolidated subsidiaries, the federal income tax liability of such
      consolidated group shall be allocated and shared among WMBfsb, WMB, NACI,
      Aristar, Inc., and each Subsidiary as if such entities filed a separate or
      consolidated return, as the case may be.

2.    The federal income tax accounts between WMI, WMBfsb, WMB, NACI, WMBFA,
      Aristar, Inc., and each subsidiary shall be settled in the following
      manner:
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      (a)   WMBfsb, WMB, NACI, WMBFA, Aristar, Inc., and each Subsidiary shall
            make payments on account of their federal income tax liability to
            WMI in the same manner and at the same time as if such entities were
            filing separate returns or separate consolidated returns with, and
            making payment of taxes (including estimated taxes) to the Internal
            Revenue Service ("IRS").

      (b)   WMI shall pay to WMBFA, WMBfsb, WMB, NACI, Aristar, Inc., and each
            Subsidiary amounts that may be due them on account of (i) any
            overpayment of their said tax liability for a taxable year or (ii)
            any credit that may result from the utilization of their net
            operating loss for a taxable year, such credit being determined in
            accordance with the provisions of item 1 above, within 30 days after
            the consolidated return is filed for that taxable year or, to the
            extent any such amount due must be recovered from the IRS, within 30
            days after payment is received from the IRS, or, if the amount due
            represents an overpayment of estimated tax which is in excess of
            WMBFA's, WMBfsb's, WMB's, NACI's, Aristar, Inc.'s or a Subsidiary's
            estimated allocable share of the consolidated federal income tax
            liability for the year, then such excess shall be paid by WMI within
            30 days of receipt from WMBFA, WMBfsb, WMB, NACI, Aristar, Inc., or
            the Subsidiary of a written explanation of the overpayment.

3.    For all taxable years during which WMBfsb, WMB, NACI, WMBFA, Aristar,
      Inc., or any Subsidiary is included in a combined or consolidated tax
      return with WMI or another of its subsidiaries, the state or other local
      tax liability of such combined or consolidated group shall be allocated
      to:

      (a)   WMBfsb, WMB, NACI, WMBFA, Aristar, Inc., and each Subsidiary as if
            each of WMBfsb, WMB, NACI, WMBFA, and such other Subsidiary had
            filed a separate, combined or consolidated tax return with each of
            its respective subsidiaries and

      (b)   WMI to the extent the sum of the amounts determined pursuant to
            clause (a) is different from the liability of the combined or
            consolidated group.

      In no event will the foregoing allocation result in treatment less
      favorable to WMBfsb, WMB, WMBFA, and their subsidiaries than if they had
      filed separate, combined or consolidated tax returns, as the case may be.

4.    The state and other local tax accounts between WMI, WMBfsb, WMB, NACI,
      WMBFA, Aristar, Inc., and each Subsidiary shall be settled in the
      following manner:

      (a)   WMBfsb, WMBFA, NACI, Aristar, Inc., and each Subsidiary shall make
            payments on account of their state and other local tax liability to
            WMB in the same manner and at the same time as if such entities were
            filing separate returns or separate combined returns with, and
            making payments of taxes (including estimated taxes) to such state
            or other local taxing authority. WMB shall compute its state and
            other local tax liability in the same manner and at the same time as
            if such it were filing a separate return with, and making payment of
            taxes (including estimated taxes) to such state or other local
            taxing authority.

      (b)   WMI shall make payments to WMB in an amount necessary to satisfy the
            state and other local tax liability after considering the payments
            computed in (a) above.

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      (c)   WMB shall pay to WMI, WMBfsb, WMBFA, NACI, Aristar, Inc., and each
            Subsidiary amounts that may be due them on account of (i) any
            overpayment of their said tax liability for a taxable year or (ii)
            any credit that may result from the utilization of their net
            operating loss for a taxable year, such credit being determined in
            accordance with item 3 above, within 30 days after the combined or
            consolidated return is filed for that taxable year or, to the extent
            any such amount due must be recovered from any state or other local
            taxing authority, within 30 days after payment is received from such
            state or other local taxing authority, or, if the amount due
            represents an overpayment of estimated tax which is in excess of
            WMI's, WMBfsb's, WMBFA's, NACI's, Aristar, Inc.'s, or a Subsidiary's
            estimated allocable share of the or combined State or local tax
            liability for the year by more than 10%, then such excess shall be
            paid by WMB within 30 days of receipt from WMI, WMBfsb, WMBFA, NACI,
            Aristar, Inc., or the subsidiary of a written explanation of the
            overpayment

5.    Deferred tax assets and liabilities of WMI, WMBfsb, WMB, NACI, WMBFA,
      Aristar, Inc., and each Subsidiary will be handled in a manner consistent
      with Statement of Financial Accounting Standards No. 109 and, as it
      relates to WMBfsb, WMB, and WMBFA, consistent with bank and thrift
      regulatory guidelines. A copy of the current regulatory guidelines is
      attached hereto as Exhibits A and B.

6.    This agreement shall remain in full force and effect until modified or
      amended by the mutual agreement of the parties hereto.

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
this date first above written:

Washington Mutual, Inc.                    New American Capital, Inc.

By /s/ KERRY KILLINGER                     By /s/ KERRY KILLINGER
   ------------------------------------       --------------------------------
   Kerry Killinger, Chairman, President       Kerry Killinger, President
   and Chief Executive Officer


Washington Mutual Bank fsb                 Aristar, Inc.

By /s/ KERRY KILLINGER                     By /s/ CRAIG CHAPMAN
   ------------------------------------       ----------------------------------
   Kerry Killinger, President                 Craig J. Chapman, President


Washington Mutual Bank                     Washington Mutual Bank, FA

By /s/ WILLIAM A. LONGBRAKE                By /s/ WILLIAM A. LONGBRAKE
   ------------------------------------       ----------------------------------
   William Longbrake, Vice Chair and          William Longbrake, Vice Chair and
   Chief Financial Officer                    Chief Financial Officer