<PAGE>

            GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
                         NUMBER ON SUBSTITUTE FORM W-9

   Guidelines for Determining the Proper Name and Identification Number to Give
the Payer.--Social Security numbers have nine digits separated by two hyphens:
i.e. 000-00-0000. Employer identification numbers have nine digits separated by
only one hyphen: i.e. 00-0000000. The table below will help determine the name
and number to give the payer.

<TABLE>
- -------------------------------------------------
<CAPTION>
                                    Give the
For this type of account:           NAME and
                                    SOCIAL SECURITY
                                    NUMBER of--
- ---------------------------------------------------
<S>                                 <C>
 1. Individual                      The individual

 2. Two or more individuals         The actual owner
    (joint account)                 of the account or,
                                    if combined
                                    funds, the first
                                    individual
                                    on the account(1)
 3. Custodian account of a          The minor(2)
    minor (Uniform Gift to
    Minors Act)

 4. a. The usual revocable          The grantor-
       savings trust account        trustee(1)
       (grantor is also trustee)
    b. So-called trust account      The actual
       that is not a legal or       owner(1)
       valid trust under state law

 5. Sole proprietorship             The owner(3)
</TABLE>
<TABLE>
<CAPTION>
                                    Give the
For this type of account:           NAME and
                                    EMPLOYER ID.
                                    NUMBER of--
- ------------------------------------------------
<S>                                 <C>
 6. Sole proprietorship             The owner(3)

 7. A valid trust, estate, or       Legal entity(4)
    pension trust

 8. Corporate                       The corporation

 9. Association, club,              The organization
    religious, charitable,
    educational or other tax-
    exempt organization

10. Partnership                     The partnership

11. A broker or registered          The broker or
    nominee                         nominee

12. Account with the                The public entity
    Department of Agriculture
    in the name of a public
    entity (such as a state or
    local government, school
    district, or prison) that
    receives agricultural
    program payments
</TABLE>
- --------------------------------------- ---------------------------------------

(1) List first and circle the name of the person whose number you furnish. If
    only one person on a joint account has a SSN, that person's number must be
    furnished.
(2) Circle the minor's name and furnish the minor's social security number.
(3) You must show your individual name, but you may also enter your business or
    "doing business as" name. You may use either your Social Security Number or
    Employer Identification Number.
(4) List first and circle the name of the legal trust, estate, or pension
    trust. (Do not furnish the taxpayer identification number of the personal
    representative or trustee unless the legal entity itself is not designated
    in the account title.)

Note: If no name is circled when more than one name is listed, the number will
      be considered to be that of the first name listed.
<PAGE>

            GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
                         NUMBER ON SUBSTITUTE FORM W-9
                                    Page 2

Obtaining a Number
If you do not have a taxpayer identification number, apply for one
immediately. To apply for a social security number, get Form SS-5, Application
for Social Security Card, from your local Social Security Administration
office. Get Form W-7, Application for Internal Revenue Service Individual
Taxpayer Identification Number, to apply for an individual taxpayer
identification number or Form SS-4, Application for Employer Identification
Number, to apply for an employer identification number. You can get Form W-7
and SS-4 from the Internal Revenue Service.

Payees Exempt from Backup Withholding
The following is a list of payees specifically exempt from backup withholding
on all payments include the following:
 (1) A corporation.
 (2) An organization exempt from tax under section 501(a), any IRA, custodial
account under section 403(b)(7) if the account satisfies the requirements of
section 401(f)(2).
 (3) The United States or any of its agencies or instrumentalities.
 (4) A state, the District of Columbia, a possession of the United States, or
any of their political subdivisions or instrumentalities.
 (5) A foreign government, or any of its political subdivisions, agencies or
instrumentalities.
 (6) An international organization or any of its agencies or
instrumentalities.
 (7) A foreign central bank of issue.
 (8) A dealer in securities or commodities required to register in the United
States, the District of Columbia or a possession of the United States.
 (9) A real estate investment trust.
 (10) An entity registered at all times during the tax year under the
Investment Company Act of 1940.
 (11) A common trust fund operated by a bank under section 584(a).
 (12) A financial institution.
 (13) A middleman known in the investment community as a nominee or custodian.
 (14) A trust exempt from tax under section 664 or described in section 4947.
Payments of dividends and patronage dividends not generally subject to backup
withholding include the following:
 (1) Payments to nonresident aliens subject to withholding under Section
4947(a)(1) of the Code.
 (2) Payments to partnerships not engaged in a trade or business in the U.S.
and which have at least one nonresident partner.
 (3) Payments of patronage dividends where the amount received is not paid in
money.
 (4) Payments made by certain foreign organizations.
 (5) Section 404(k) payments made by an ESOP.
Payments of interest not generally subject to backup withholding include the
following:
 (1) Payments of interest on obligations issued by individuals. NOTE: You may
be subject to backup withholding if this interest is $600 or more and is paid
in the course of the payer's trade or business and you have not provided your
correct taxpayer identification number to the payer.
 (2) Payments of tax-exempt interest (including exempt-interest dividends
under Section 852 of the Code).
 (3) Payments described in Section 6049(b)(5) of the Code to non-resident
aliens.
 (4) Payments on tax-free covenant bonds under Section 1451 of the Code.
 (5) Payments made by certain foreign organizations.
 (6) Payments made to a nominee.
 (7) Mortgage interest paid to you.
EXEMPT PAYEES DESCRIBED ABOVE SHOULD FILE FORM W-9 TO AVOID POSSIBLE ERRONEOUS
BACKUP WITHHOLDING. FILE THIS FORM WITH THE PAYER, FURNISH YOUR TAXPAYER
IDENTIFICATION NUMBER, WRITE "EXEMPT" IN PART 2 OF THE FORM, SIGN AND DATE THE
FORM, AND RETURN IT TO THE PAYER. IF YOU ARE A NONRESIDENT ALIEN OR A FOREIGN
ENTITY NOT SUBJECT TO BACKUP WITHHOLDING, GIVE THE PAYER A COMPLETED FORM W-8,
CERTIFICATE OF FOREIGN STATUS.
Certain payments other than interest, dividends, and patronage dividends that
are not subject to information reporting are also not subject to backup
withholding. For details, see the regulations under Section 6041, 6041A(a),
6042, 6044, 6045, 6049, 6050A and 6050N of the Code and the regulations
promulgated thereunder.
Privacy Act Notice.--Section 6109 requires most recipients of dividend,
interest, or other payments to give your correct taxpayer identification
numbers to payers who must report the payments to IRS. The IRS uses the
numbers for identification purposes. Payers must be given the numbers whether
or not recipients are required to file tax returns. Payers must generally
withhold 31% of taxable interest, dividend, and certain other payments to a
payee who does not furnish a taxpayer identification number to a payer.
Certain penalties may also apply.

Penalties
(1) Failure to Furnish Taxpayer Identification Number.--If you fail to furnish
your correct taxpayer identification number to a payer, you are subject to a
penalty of $50 for each such failure unless your failure is due to reasonable
cause and not to willful neglect.
(2) Civil Penalty for False Information With Respect to Withholding.--If you
make a false statement with no reasonable basis which results in no imposition
of backup withholding, you are subject to penalty of $500.
(3) Criminal Penalty for Falsifying Information.--Willfully falsifying
certifications or affirmations may subject you to criminal penalties including
fines and/or imprisonment.
FOR ADDITIONAL INFORMATION CONTACT YOUR TAX CONSULTANT OR THE INTERNAL REVENUE
SERVICE.