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                                                                 Exhibit 99(Z)

ONEBEACON

OVERVIEW

       On June 1, 2001 a wholly-owned subsidiary of White Mountains Insurance
Group, Ltd. ("White Mountains") acquired OneBeacon Corporation ("OneBeacon",
formerly CGU Corporation) from London-based CGNU plc ("CGNU"). The consolidated
financial statements of OneBeacon for the first five of the six months ended
June 30, 2001, the six months ended June 30, 2000 and the years ended December
31, 2000, 1999 and 1998 were prepared in their entirety under the direction of
the former management of OneBeacon, and for the benefit of, CGNU. The
consolidated financial statements of OneBeacon for the one month ended June 30,
2001 were prepared in their entirety under the direction of, and for the benefit
of, White Mountains and its subsidiaries.

       The preparation of financial statements in conformity with accounting
principles generally accepted in the United States ("GAAP") requires management
to make estimates and assumptions, which are based on information known as of
the date the financial statements are prepared and issued, that affect the
reported amounts of assets, liabilities, revenues and expenses. Eventual results
can differ from those estimates, particularly with respect to loss and loss
adjustment expense reserves, as further information subsequently unfolds.
OneBeacon's financial results for the year ended December 31, 2000 included
$818.0 million of loss and loss adjustment expenses related to events that were
determined to have occurred in prior accident years. As a result, loss and loss
adjustment expense reserves for the years ended December 31, 1999 and 1998, as
presented herein, were subsequently proven to be inadequate.

       These historic financial statements are not necessarily indicative of
financial results expected in future periods and should be read in conjunction
with the Company's Form 8-K filed on June 25, 2001 which contains certain
historical and pro forma financial information of White Mountains and OneBeacon.

       On September 25, 2000, in connection with its pending acquisition by
White Mountains, OneBeacon determined that it would sell its life insurance
operations, its Canadian property and casualty operations and certain other
non-insurance operations to its parent, CGNU plc, immediately prior to White
Mountains' acquisition of OneBeacon on June 1, 2001. Accordingly, these
discontinued operations have been excluded from OneBeacon's continuing
operations herein.

       On June 1, 2001, immediately prior to and in connection with its
acquisition of OneBeacon by White Mountains, CGNU caused OneBeacon to
purchase $2.5 billion in reinsurance protection for its asbestos,
environmental and certain other latent exposures with National Indemnity
Company (the "NICO Cover") and $400.0 million of adverse loss development
reinsurance protection with General Re Corporation (the "GRC Cover").




SELECTED FINANCIAL DATA

       Selected consolidated financial data of OneBeacon for the one month
period ended June 30, 2001, the six month periods ended June 30, 2001 and 2000
and the years ended December 31, 2000, 1999 and 1998 follows:

<Table>
<Caption>
------------------------------------------------------------------------------------------------------------------------------
                                               ONE MONTH          SIX MONTHS
                                                 ENDED               ENDED                        YEAR ENDED
                                               JUNE 30,            JUNE 30,                      DECEMBER 31,
                                                             ------------------------   --------------------------------------
Dollars in Millions                              2001(1)         2001        2000          2000          1999         1998
                                               -----------   -----------  -----------   -----------   -----------   ----------
                                                                                                  
INCOME STATEMENT DATA:
Net written insurance premiums(2)              $     314.5   $     563.1  $   2,274.4   $   4,294.1   $   4,248.7   $  4,113.4
                                               ===========   ===========  ===========   ===========   ===========   ==========

Net earned insurance premiums(2)               $     330.0   $     726.8  $   2,157.0   $   4,275.1   $   4,260.0   $  4,041.9
Loss and loss adjustment expenses (2)               (308.5)       (841.7)    (1,640.5)     (4,302.0)     (3,252.4)    (3,946.9)
Other underwriting expenses                         (106.2)       (777.9)      (642.6)     (1,425.2)     (1,443.8)    (1,461.5)
                                               -----------   -----------  -----------   -----------   -----------   ----------
  Underwriting loss                                  (84.7)       (892.8)      (126.1)     (1,452.1)       (436.2)    (1,366.5)
Net investment income                                 38.5         267.8        243.3         504.9         502.1        480.3
Net realized gains from sales of investments           3.7         326.3         43.0         732.8         381.9        400.3
Interest expense                                      (0.1)        (33.1)       (36.4)        (72.6)        (72.7)        (1.3)
                                               -----------   -----------  -----------   -----------   -----------   ----------
  Pretax income (loss)                               (42.6)       (331.8)       123.8        (287.0)        375.1       (487.2)
Income tax benefit (provision)                        15.2          68.0        (24.0)         83.3        (104.5)       186.1
                                               -----------   -----------  -----------   -----------   -----------   ----------
Net income (loss) from continuing operations   $     (27.4)  $    (263.8) $      99.8   $    (203.7)  $     270.6   $   (301.1)
                                               ===========   ===========  ===========   ===========   ===========   ==========
GAAP RATIOS:
Loss and loss adjustment expense(3)                     94%       n/m              76%          101%           76%          98%
Other underwriting expense(3)                           32%       n/m              30%           33%           34%          36%
                                               -----------   -----------  -----------   -----------   -----------   ----------
  Combined(3)                                          126%       n/m             106%          134%          110%         134%
                                               ===========   ===========  ===========   ===========   ===========   ==========
BALANCE SHEET DATA (END OF PERIOD):
Total assets                                                 $  15,097.5  $  13,887.8   $  14,210.1   $  14,000.2   $ 14,557.4
Long-term debt                                                       3.2      1,130.8       1,113.9       1,130.8      1,126.0
Shareholders' equity                                             3,249.9      3,866.7       3,198.7       3,771.5      3,979.8
------------------------------------------------------------------------------------------------------------------------------
</Table>


(1) White Mountains acquired OneBeacon on June 1, 2001. As a result, White
Mountains' results of operations for the 2001 second quarter included
OneBeacon's results only for the one-month period ended June 30, 2001. These
results were reported in White Mountains' Form 10- Q for the six months ended
June 30, 2001.

(2) Net written insurance premiums, net earned insurance premiums and loss and
loss adjustment expenses for the six months ended June 30, 2001 were
significantly effected by the NICO Cover and the GRC Cover which were entered
into by OneBeacon on June 1, 2001.

(3) As a result of entering into the NICO Cover and the GRC Cover on June 1,
2001, OneBeacon's combined ratio for the six months ended June 30, 2001 is not
considered to be meaningful ("n/m"). The combined ratio, calculated without
taking into account these reinsurance covers, was approximately 119%.




SIX MONTHS ENDED JUNE 30, 2001 COMPARED TO SIX MONTHS ENDED JUNE 30, 2000

       OneBeacon reported a net loss from continuing operations of $263.8
million for the six months ended June 30, 2001 versus net income from continuing
operations of $99.8 million for the comparable 2000 period. The decline in net
income during the 2001 period related principally to the cost of the NICO Cover
and the GRC Cover. As a result of these significant reinsurance covers,
OneBeacon's combined ratio for the six months ended June 30, 2001 is not
considered to be meaningful. The combined ratio, calculated without taking into
account these covers, was approximately 119%. OneBeacon's reported combined
ratio for the six month period ended June 30, 2000 was 106%. Favorable
underwriting results recorded during the six months ended June 30, 2000 were
influenced by reserve levels that were subsequently determined to be inadequate
as evidenced by significant reserve strengthening recorded in future periods.

       Net written premiums for the six months ended June 30, 2001 decreased
significantly to $563.1 million versus $2,274.4 million in the comparable
2000 period. Earned premiums also decreased significantly to $726.8 million
in the 2001 period versus $2,157.0 million in the 2000 period. These
decreases in net premiums relate primarily to $1,510.1 million in
reinsurance premiums ceded and paid in connection with the NICO Cover and the
GRC Cover.

       Loss and loss adjustment expenses for the six months ended June 30, 2001
decreased significantly to $841.7 million versus $1,640.5 million in the
comparable 2000 period. This $798.8 million decrease resulted primarily from
$1,037.8 million in loss and loss adjustment expenses ceded pursuant to the NICO
Cover and the GRC Cover.

       Other underwriting expenses increased $135.3 million to $777.9 million
for the six months ended June 30, 2001 versus $642.6 million in the comparable
2000 period. This increase resulted principally from the immediate recognition
of certain deferred policy acquisition costs considered to be unrecoverable in
future periods due to poor underwriting results experienced during 2001 and
2000. In addition, other underwriting expenses increased during the 2001 period
relating to employee benefit obligations, reserves established for uncollectible
receivable balances, write-offs of non-utilizable software costs and litigation
reserves recorded in the normal course of business.

       Net investment income for the six months ended June 30, 2001 increased
modestly to $267.8 million versus $243.3 million in the 2000 period. This $24.5
million increase resulted from a decision made by OneBeacon during the 2000
fourth quarter and 2001 first quarter to liquidate a large portion of its common
equity portfolio in favor of additional investments in fixed maturities. This
action resulted in an increase in net investment income earned during the 2001
first half versus the 2000 comparable period.

       Net realized gains from sales of investment securities for the six months
ended June 30, 2001 increased significantly to $326.3 million versus $43.0
million in the 2000 period. This $283.3 million increase resulted from the sale
of a large portion of OneBeacon's common equity portfolio during the 2001 first
quarter.

       Interest expense for the six months ended June 30, 2001 decreased to
$33.1 million versus $36.4 million in 2000. This $3.3 million decrease
resulted largely from the repayment of OneBeacon's $1.1 billion intercompany
loan with CGNU on June 1, 2001.

       OneBeacon's income tax benefit for the six months ended June 30, 2001 of
$68.0 million represented an effective tax rate of 20.5%. OneBeacon's income tax
expense of $24.0 million for the six months ended June 30, 2000 represented an
effective tax rate of 19.4%. OneBeacon's effective rate of tax benefit for the
2001 first half (resulting from a net loss reported during that period) was less
than the statutory rate of 35% as a result of establishing deferred tax
valuation allowances during the period which more than offset the effects of tax
exempt interest on certain fixed maturity securities and dividends received
deductions on dividends relating to certain equity securities. OneBeacon's
effective tax rate for the 2000 first half was less than the statutory rate of
35% due to the effects of tax exempt interest on certain fixed maturity
securities and dividends received deductions on dividends relating to certain
equity securities.




YEAR ENDED DECEMBER 31, 2000 COMPARED TO YEAR ENDED DECEMBER 31, 1999

       OneBeacon reported a net loss from continuing operations of $203.7
million for the year ended December 31, 2000 versus net income from continuing
operations of $270.6 million for the comparable 1999 period. The decline in net
income in 2000 related principally to an $818.0 million increase in loss and
loss adjustment expense reserves recorded during that period relating to prior
accident year losses, partially offset by an increase in net realized gains from
sales of investment securities. OneBeacon's reported combined ratio for 2000 was
134% versus 110% for 1999.

       Net written premiums from 1999 to 2000 increased slightly to $4,294.1
million in 2000 versus $4,248.7 million in 1999. Net earned premiums also
increased slightly to $4,275.1 million in 2000 versus $4,260.0 million in 1999.
The net $15.1 million increase in net earned premiums was comprised of a $35.8
million increase in premiums relating to commercial lines, a $27.4 million
increase relating to specialty lines and a $48.1 million decrease relating to
personal lines.

       Commercial lines net earned premiums increased in 2000 primarily as a
result of overall price increases but were offset slightly by management's
decision to non-renew accounts considered to have performed poorly and by
premiums ceded in connection with certain reinsurance coverages. Specialty lines
net earned premiums increased in 2000 as OneBeacon increased its focus on
specialty writings at this time. However, incurred losses on this business line
were later determined to be much higher than originally anticipated which
prompted OneBeacon to discontinue writing many of its specialty products in
2001. Personal lines net earned premiums declined in 2000.

       OneBeacon's loss and loss adjustment expenses increased $1,049.6 million
to $4,302.0 million in 2000 versus $3,252.4 million in 1999. The increase in
loss and loss adjustment expenses resulted primarily from $818.0 million of
adverse loss development recorded during 2000 relating to prior accident years
as compared to $57.5 million of adverse development recorded during 1999. The
adverse loss development recorded during 2000 related primarily to exposures in
the areas of auto liability coverage ($204.4 million), workers compensation
($149.3 million), general liability ($136.9 million) and special multi-peril
coverage ($256.5 million). Additionally, OneBeacon's 2000 loss and loss
adjustment expenses were higher than 1999.

       Catastrophe losses net of reinsurance decreased $44.6 million to $89.0
million in 2000 versus $133.6 million in 1999. Catastrophe losses affecting
2000 results consisted of weather related events, including severe weather in
the Northeast and the Southeast and winter storms in the Midwest. Catastrophe
losses affecting 1999 results consisted of Hurricane Floyd, severe tornado
and hail storms in the Southwest and winter storms in the Midwest and the
Northeast.

       Other underwriting expenses decreased $18.6 million to $1,425.2 million
in 2000 versus $1,443.8 million in 1999. Expenses incurred related to the merger
of Commercial Union Corporation and General Accident Corporation of America in
1999 resulted in higher other underwriting expenses in that year versus 2000
despite increases during 2000 in deferred acquisition cost expenses and
additional employee incentive costs related to the acquisition of OneBeacon by
White Mountains. The increase in 2000 deferred policy acquisition cost expenses
resulted primarily from the immediate recognition of $23.6 million of such costs
that were considered to be unrecoverable in future periods due to poor
underwriting results experienced during 2000.

       Net investment income of $504.9 million in 2000 was essentially unchanged
from $502.1 million in 1999. During the latter part of the 2000 fourth quarter
OneBeacon significantly decreased its portfolio of common equity securities in
favor of additional investments in fixed maturity investments. Due to the timing
of these changes in its investment portfolio, these actions did not have a
significant impact on the components of OneBeacon's net investment income for
2000.




       Net realized gains from sales of investment securities increased $350.9
million to $732.8 million in 2000 versus $381.9 million in 1999. During 2000,
OneBeacon recognized net realized gains of $553.9 million from sales of common
equity securities versus comparable net realized gains of $398.2 million in
1999. In addition, OneBeacon recognized net realized gains of $195.8 million
during 2000 from sales of fixed maturity securities versus comparable net
realized losses of $16.1 million in 1999. The increase in net realized gains
recognized by OneBeacon during 2000 principally resulted from a decision to
reduce its portfolio of common equity securities and to reallocate a larger
portion of its fixed maturity portfolio to U.S. Government and agency
obligations.

       Interest expense of $72.6 million in 2000 was essentially unchanged from
$72.7 million recorded in 1999. During 1999 and 2000 OneBeacon's intercompany
term loan from its parent remained at approximately $1.1 billion.

       OneBeacon's income tax benefit of $83.3 million in 2000 represented an
effective tax rate of 29.0%. OneBeacon's income tax expense of $104.5 million in
1999 represented an effective tax rate of 27.9%. OneBeacon's effective rate of
tax benefit for 2000 (resulting from a net loss reported during that year) was
less than the statutory rate of 35% as a result of establishing deferred tax
valuation allowances during the 2000 period which more than offset the effects
of tax exempt interest on certain fixed maturity securities and dividends
received deductions on dividends relating to certain equity securities.
OneBeacon's effective tax rate for 1999 was less than the statutory rate of 35%
due to the effects of tax exempt interest on certain fixed maturity securities
and dividends received deductions on dividends relating to certain equity
securities.

YEAR ENDED DECEMBER 31, 1999 COMPARED TO YEAR ENDED DECEMBER 31, 1998

       OneBeacon reported net income from continuing operations of $270.6
million for the year ended December 31, 1999 versus a net loss from continuing
operations of $301.1 million for the comparable 1998 period. The net loss
recorded during 1998 was the result of a reserve increase relating primarily to
environmental and asbestos exposures. Underwriting results recorded during the
1999 period were influenced by reserve levels that were subsequently determined
to be inadequate as evidenced by significant reserve increases recorded in 2000.
OneBeacon's reported combined ratio for 1999 was 110% versus 134% for 1998.

       Net written premiums from 1998 to 1999 increased $135.3 million to
$4,248.7 million in 1999 versus $4,113.4 million in 1998. Net earned premiums
also increased to $4,260.0 million in 1999 versus $4,041.9 million in 1998. The
$218.1 million increase in net earned premiums from 1998 to 1999 consisted of a
$155.3 million increase in premiums relating to specialty lines, a $81.0 million
increase relating to commercial lines offset by a $18.2 million decrease
relating to personal lines.

       The increase in specialty lines net earned premiums for 1999 resulted
primarily from the acquisition of National Farmers Union Property & Casualty
Company and its subsidiaries ("NFU") by OneBeacon on July 16, 1998. In addition,
specialty lines net earned premiums increased in 1999 as OneBeacon increased its
focus on specialty writings at this time. Commercial lines net earned premiums
in 1999 increased principally from increased writings of workers compensation
risks. Personal lines net earned premiums declined in 1999.

       OneBeacon's loss and loss adjustment expenses decreased $694.5 million to
$3,252.4 million in 1999 versus $3,946.9 million in 1998. The decrease in loss
and loss adjustment expenses from 1998 to 1999 resulted from lower reserves
recorded in 1999 versus 1998. During 1999 OneBeacon recorded $57.5 million of
adverse loss development. During 1998, OneBeacon increased reserves by $614.0
million relating to environmental and asbestos exposures and $226.6 million for
other lines.

       Catastrophe losses net of reinsurance decreased $44.3 million to
$133.6 million in 1999 versus $177.9 million in 1998. Catastrophe losses
affecting 1999 results consisted of Hurricane Floyd, severe tornado and hail
storms in the Southwest and winter storms in the Midwest and the Northeast.
Catastrophe losses affecting 1998 results consisted of a severe ice storm
affecting northern New England, tornado and hail storms in the Southeast and
the Midwest.




       Other underwriting expenses decreased $17.7 million to $1,443.8 million
in 1999 versus $1,461.5 million in 1998. During 1999, reductions in costs
related to the merger of Commercial Union Corporation and General Accident
Corporation of America were partially offset by an increase in expenses related
to information systems development and deferred policy acquisition costs.

       Net investment income increased $21.8 million to $502.1 million in 1999
versus $480.3 million in 1998. This increase resulted from a combination of
higher yields earned as well as a higher concentration of fixed maturity
investments during the 1999 period versus 1998.

       Net realized gains from sales of investment securities decreased $18.4
million to $381.9 million in 1999 versus $400.3 million in 1998. The decrease in
net realized gains from 1998 to 1999 came principally from net realized losses
on sales of fixed maturity investments of $16.2 million resulting from decreases
in market interest rates during the period.

       Interest expense increased $71.4 million to $72.7 million in 1999 versus
$1.3 million in 1998. The increase in interest expense during 1999 related
principally to an intercompany borrowing of $1.1 billion from OneBeacon's parent
which was undertaken in the 1998 fourth quarter.

       OneBeacon's income tax expense of $104.5 million in 1999 represented an
effective tax rate of 27.9%. OneBeacon's income tax benefit of $186.1 million in
1998 represented an effective tax rate of 38.2%. OneBeacon's effective tax rate
for 1999 was less than the statutory rate of 35% due to the effects of tax
exempt interest on certain fixed maturity securities and dividends received
deductions on dividends relating to certain equity securities. OneBeacon's
effective rate of tax benefit for 1998 (resulting from a net loss reported
during that year) was greater than the statutory rate of 35% as a result of the
effects of tax exempt interest on certain fixed maturity securities and
dividends received deductions on dividends relating to certain equity
securities.

LIQUIDITY AND CAPITAL RESOURCES

       OneBeacon's primary sources of cash are premiums, investment income,
reinsurance recoveries on paid losses, and proceeds from investment sales and
maturities. OneBeacon's primary uses of cash are claims payments, underwriting
and other operating expenses, commissions and other acquisition costs, taxes and
purchases of investment securities. The fixed maturity portfolio of OneBeacon at
June 30, 2001 consisted primarily of publicly traded, investment grade corporate
debt securities, U.S. government and agency securities and mortgage-backed
securities.

       OneBeacon maintains a portion of its investment portfolio in highly
liquid, short-term securities to provide for its immediate cash needs.

       On June 1, 2001, OneBeacon repaid its $1.1 billion intercompany term note
with CGNU immediately prior to its acquisition by White Mountains.

       On June 1, 2001, CGNU made a $200.0 million cash contribution to
OneBeacon immediately prior to its acquisition by White Mountains.

       On June 1, 2001, immediately prior to acquisition, CGNU caused OneBeacon
to purchase the NICO Cover for $1,114.8 million in cash. Pursuant to the NICO
Cover, OneBeacon obtained $2.5 billion in total coverage against its asbestos,
environmental and certain other latent exposures and ceded net nominal loss
reserves of $747.6 million.

       On June 1, 2001, immediately prior to acquisition, CGNU caused OneBeacon
to purchase the GRC Cover for $275.0 million in cash. Pursuant to the GRC Cover,
OneBeacon obtained $400.0 million of adverse development coverage.




       On June 1, 2001, immediately after the acquisition, White Mountains
contributed Folksamerica and its subsidiaries as well as certain other assets to
OneBeacon which served to increase OneBeacon's shareholders' equity at that date
by approximately $661.5 million.

       In 1998, OneBeacon's parent contributed $475.0 million in capital to
OneBeacon, consisting of $425.0 million in cash and $50.0 million in the form of
common stock of Houston General Insurance Company.

       In 1998, OneBeacon made a return of capital distribution of $1.1 billion
in cash to its parent.

       In 1998, OneBeacon borrowed $1.1 billion from its parent in the form of
an intercompany term note. The note was issued by OneBeacon Holdings LLC, a
wholly owned subsidiary of OneBeacon's ultimate parent and direct owner of 45.9%
of OneBeacon's common stock. In addition to its intercompany debt with OneBeacon
Holdings LLC, OneBeacon also had third-party debt of $13.9 million and $30.8
million at December 31, 2000 and 1999, respectively.

       In 1998, OneBeacon purchased NFU for $116.4 million in cash.

       OneBeacon's ability to pay dividends to its shareholder is dependent on
the receipt of dividends from its insurance subsidiaries. In a given calendar
year, OneBeacon's insurance subsidiaries can generally dividend the greater of
10% of their statutory surplus at the beginning of the year or the prior year's
statutory net income without prior regulatory approval subject to the
availability of unassigned funds (the statutory accounting equivalent of
retained earnings). Larger dividends can be paid only upon regulatory approval.
During the six months ended June 30, 2001 and the years ended December 31, 2000,
1999 and 1998, OneBeacon declared and subsequently paid dividends totalling
$53.5 million, $342.3 million, $180.1 million and $302.8 million, respectively.