Failure Knowledge Database / 100 Selected Cases

Mizuho Financial Group Banking System Failure
April 1 through early May in 2002 at Mizuho Bank
Masayuki Nakao (Institute of Engineering Innovation, School of Engineering, the University of Tokyo)
The s erious banking sy stem problems disr upted t he n ew banks’ op erations foll owing the A pril 1 launch ofMizuho Ban k and Mi zuho Corporate Bank in to which D ai-ichi Kangy o Bank Lt d., Fuji B ank Ltd. andIndustrial Bank of Japan Ltd. had been consolidated under the management of Mizuho Holding in Tokyo. The
Mizuho Bank’s important first day in business was tarnished by the ATM (automatic teller machine) transaction
errors and d elayed auto matic d ebits for u tility a nd credit card bills. The bigg est banking sy stem f ailure inhistory caus ed ch aos, fro m wh ich the recovery t ook more th an one mon th until t he b ank’s o perations wentcompletely back to normal. A long period of f ailed discussion among the three banks about whose computer
systems wo uld su rvive the merger l eft i nsufficient ti me for t he im plementation p eriod o f a re lay s ystem t obridge the ban king sy stems. The b ank group w ent ahea d w ith in tegration and th e op eration of th e unif iedbanking sy stem, d espite the tes ting p eriod of the unifi ed oper ation wa s n ot l ong enough fo r the lar ge-scale
operation.
1. Event
As part of the finance-industry reorganization, Dai-ichi Kangyo Bank Ltd., Fuji Bank Ltd. and Industrial
Bank of Japan Ltd. were consolidated into Mizuho Bank Ltd. and Mizuho Corporate Bank Ltd. under the
management of Mizuho Ho lding in Tokyo. The new Mizuho Bank’s first day in business (April 1, 2002)
was tarnished by the ATM (automatic teller machine) transaction errors in whi ch debits were made fromaccounts althou gh cu stomers did not receive cash from th e m achine, as well as un processed scheduled
automatic debits for utility and credit card bills. The banking system failed to process 105,000 automatic
debits s cheduled for April 1. Delay ed d ebits backlogged, and the n umber o f delayed deb its reached 2.5
million by the end of April 5. An additional 30,000 double debits were found between April 1 and April 5.
The biggest banking system failure in histo ry caused chaos, from which the recovery took more than one
month until the bank’s operations went completely back to normal.
2. Course
On Aug ust 20, 1999, Dai- Ichi Kangyo B ank, Fuji Ba nk and Industrial Bank o f Japan an nounced awide-ranging alliance to create the world's largest bank through a joint holding company.
In De cember 1999, the ba nks agr eed on the pla n to i ntegrate the e ntire Mizu ho Bank system, whichprimarily ser ves in dividuals a nd small and medium-sized companies, on the existing D ai-ichi Kangyo
Bank system in April 2002.
Mizuho Holding Inc. was established on September 29, 2000, as the holding company of Mizuho Financial
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Failure Knowledge Database / 100 Selected Cases
group, to become the integrated body of Dai-Ichi Kangyo Bank, Fuji Bank and Industrial Bank of Japan.
In De cember 2 000, th e banks r eviewed th eir origina l plan of ba nking sy stem in tegration and agreed on
postponing it until April 2003 and interfacing the three banks’ systems. The in terface scheme would takethe Dai -ichi Kangyo Ban k s ystem as the prim ary b anking sy stem, an d a relay system for bridgin g the
primary system and the two banking systems of Fuji Bank and Industrial Bank of Japan.
However, the program add ed to handle logical co nnection between the pr imary system and the relay
systems had a bug that would cause a specific problem in certain circumstances. The bug was undetectedduring the connection and load tests conducted prior to the banking operation on April 1.
The relay system plan was adopted unanimously by the Mizuho Holdings board on May 10, 2001.
The Financial Services Agency (FSA) evaluated the integration scheme of the Mizuho Financial Group’s
new ban ks fro m March through June 2001. I t ex pressed concern ab out the d elay i n prepa ration fo r t hescheduled integration and reminded the company of the issues of its integration scheme.
In December 2001, the banks agreed that among the Mizuho Corporate Bank branches, the ones running
the Dai- ichi Kangyo Bank s ystem would proc ess data o f mo re than 5 0,000 accounts includ ing large
corporations and financial institutions, instead of the ones running the Industrial Bank of Japan’s system.
The original plan specified the Bank of Japan’s system to process the data; however, it was later found thatthe system was not well suited for mass data processing.
The banks notified their corporate customers of the changes in the bank and the branch codes effective on
April 1, an d req uested appropriate chan ges to b e made to the ir s cheduled transactions as we ll a s to thetransactions d ata in t he Japanese Bankers Association f ormat. Fuji Bank an d Industria l Ban k of Ja pan
would take the bank code o f Dai-ich i K angyo Ban k, an d so me branch co des would change o n April 1,
2002.
In early March 2002, the engineers tested the integrated banking system for debit transactions.
On March 22, the Mizuho Holding management committee received from the banking system division thestatus report saying that preparation for the new banking system was coming along almost as scheduled. It
decided to go ahead with the scheduled integration of banking systems.
The eng ineers di d not thoroughly test th e n ew sy stem for it s ov erall pr ocessing load i n a lar ge-scale
operation with various transaction requests, including requests of invalid debit transactions, because there
was not enough time to conduct such an exhaustive test.
The banks started processing account data on March 30, two day s before the first day of the new banks inbusiness. The batch pro cesses fo r all ocating data to the t hree ba nking s ystems we re i nterrupted bymismatches of bank an d branch codes because of ac count data containing both the old and new codes. A
programming bug also cau sed errors during process ing deb it transact ion data i n non-FSA formats.
Although the program was m anually debugged, processing w as d elayed, resulting in more than 50,0 00
unprocessed account and transaction data. The b ank grou p w ent ah ead w ith th e s cheduled sy stem
integration, assuming tha t the d elay in dat a pr ocessing wo uld not affect on the ne w banks’ operations as
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Failure Knowledge Database / 100 Selected Cases
long as all would be completed processing by the end of April 1.
On April 1, the th ree bank s were officially and legally combined into two co mpanies, Mizuho Bank andMizuho Corporate Bank. ATM transaction errors started to occur at the Mizuho Bank branches. The ATMs
at branches formerly operated by Fuji Bank only accepted the ATM cards provided by the former Fuji Bank.
While customers had no pr oblem with the former Fuji Bank ATM cards at br anches formerly operated by
Fuji Bank, ATMs at other new Mizuho Bank branches dispensed no cash although debits were made fromthe accounts.
Mizuho Bank disconnected the relay systems from the prim ary banking system. It found the cause of the
ATM transaction errors at around 13:00.
While operators manually cor rected th e transaction and money r emittance e rrors, mo re tha n 100,000
automatic debits were backlogged.
This inadvisable manual correction resulted in another issue, loss of account data, to aris e. The bank later
discovered that the confidential data of account holders were accidentally disposed of.
On April 2, the ATM systems were restored.
On April 4, the bank reported publicly the delay in automatic debits.
On April 5 , the bank reported 2 .5 million dela yed debits s ince April 1. More than 30,0 00 d ouble debits
were found.

Figure 1. Banking System Integration Scheme
On April 8, an additional 30,000 double debits were found (restored by April 9)
On April 9, the backl og of auto mated debits was reduced to 150,000. The president of Mizuho Holdings
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Failure Knowledge Database / 100 Selected Cases
had a pr ess co nference after he t estified in acongressional hearing tha t th e b ank would be able tonormalize operations in April.
On April 11, additional delayed debits were found, resulting in a backlog increase to 400,000.
On April 18 , the backlog of automated debits was cleared except fo r a su bstantial delay in forwarding ofcredit advices.
On April 30, month-end 12 million automatic debits were processed normally as scheduled.
On May 8, FSA and the Bank of Japan decided to conduct an emergency inspection.
On May 21, FSA dispatched the financial regulator to inspect Mizuho Bank on-site.
On May 21, the president of Mizuho Holdings said at a press conference that the bank was expecting a lossof 1.8 billion yen attributed to the banking system failure.
3. Cause(1) Technical factor (direct cause)a.

ATM transaction errors
The Mizuho B ank’s p rimary b anking s ystem (p revious D ai-ichi Kan gyo B ank s ystem us ing th e
Fujitsu mainframe) was not modified properly.
The pr ogram added to h andle logical co nnection be tween the pr imary system an d t he r elay
systems ha d a bug t hat ca used a specific problem in certain c ircumstances. It was an ov ersightduring the program development.

b. Delay ed automatic debits• Invalid information in the transaction request data.
• A bug in the program developed for processing debits transaction for bridged banking network.
The pr oblems surfaced onl y unde r certain co nditions such as “data of d ifferent types or
categories are combi ned in a c ertain manner d uring pr ocessing” when “data overflow orexcessive transactions accumulated in the data storage area for the relay computer”.
The first bug fix failed to correct the programming errors and caused the recurrence of the online
banking system failure on April 8.
c.

Insufficient testing period of the unified operation and load tests.
Program development always accompany bugs. Thorough operational testing and debugging werecritical for the unified system before bringing them on-line. Testing should have simulated the reallarge scale banking operation and various complicated situations.

(2) Corporative factor (principal cause)a.

Delayed decision on the system integration scheme (problems during planning)
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Failure Knowledge Database / 100 Selected Cases
The mer ger lacked the dominating par ty that c an effectively take char ge, and the thr ee banks
simply could not agree

on whos e co mputer systems wo uld survive the merger. The sy stem

integration scheme changed a few times until the three banks reached a settlement.
The three banks should have proposed the most adequate scheme after assessing the requirementson th e unified b anking sy stem and evaluat ing the exist ing b anking s ystems o f the th ree ban ks.
Instead o f determining the system t hat w ould s urvive the merger, the thr ee banks kno cked ou t acompromise, involv ing rel ay systems t o sim ply bridge the exis ting sy stems o f t he three banks.
This tem porizing s cheme involving re lay s ystems was not inadequat e i tself; however, delay indecision making resulted in insufficient period for testing and systems integration.
The scheme l acked t he ar chitecture concept. W hen making changes in ba nking systems such as
integration, i t is bes t t o ch oose t he ti me of year when processing v olume is s maller. Apr il 1 ha s
been u sually the busiest d ay of th e y ear fo r t he three b anks, and s cheduling sy stem changes onsuch a day was n ot advisable. I n add ition, th e thr ee banks that m erged i nto Mizuho were too
fixated on their schedule to perfect the systems integration, which compounded the problem.
b. Delay in preparations for system integration
Problematic management organization for the integration project.
The Mizuho Hol ding man agement co mmittee did no t receive a ccurate st atus reports i n a timely
manner, while there had been evident delays in pr eparation for the scheduled system integration.
The three b anks i ndependently per formed pr eparation towards the s cheduled sy stem i ntegration
without reporting status to each other or to the holding company.
The CEOs ( chief executive off icer) of th e three banks kn ew o f the delay aft er r eceiving several
reports in 200 1 fro m their bank ing system divisions. The CE Os simply i nstructed th eir ban kingsystem divisions to make up for the delay without looking into details.
c.

The br idging systems wer e not tes ted thoroughly for the ir per formance and pr ocessing load s
before bringing them on-line.

d. The Mizuho Holding management committee went ahead with integration and the operation of theunified ba nking sy stem, de spite the delay in pr eparation a nd r isks of system f ailures dur ing t hereal banking operation.
4. Immediate Action(1) FSA di spatched the fi nancial re gulators to in spect M izuho B ank, and th e Bank of J apan in spected
Mizuho Holding and Mizuho Corporate Bank on-site. The inspections took a month to investigate thecause of banking system failures and reviewed the handling of problems as well as the banks’ measuresfor preventing recurrences of system failures.
(2) FSA issued a business improvement administrative order to Mizuho Holding.
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Failure Knowledge Database / 100 Selected Cases
The order includes measures for preventing system failures and responses, as well as improvement in
administration an d un ified b anking sy stem to help preventing recurrences of system failures andclarifying management’s responsibility.
Because of th e estimated large su m of develo pment cost for the unified ban king system an d ris ks ofsystem failures during the development, it called for drastic prevention measures such as improvement
in management of sy stem d evelopment and ad ministration, reor ganization o f the b anking system
division, reinforcement of th e auditing sy stem, active inv olvement of t he management committee inthe system development project, better communication and information sharing among the three banks.
FSA also ordered to create guidelines that enable prompt responses and adequate resolutions to system
failures. Although Mizuho had guidelines for actions in cas e of system failures prior to the merger in
April, they la cked c ustomer-oriented instructions of how to r espond to i ndividuals and corporate
customers and announce schedules of restoration.
5. Countermeasure(1) In response to the system failures, Mizuho formed the system failure special committee that includes
outside consultants.
(2) Establishment of corporate governance system
Rivalry and power struggle among the three banks resulted in delay of the schedule and contributed tothe system failures. Such organizational issues must be eliminated to construct efficient management
systems.
Mizuho pr oposed r eorganization of its administrative str ucture to consolidate s ound and e fficientmanagement.
Some management officers of the three banks was to be let go to make th e reporting system efficientso that Mizuho Holding can control the banks’ operations.
The management committees of the new banks were previously structured to include equal number ofofficers from the three banks as a compromise to the rivalry and power struggle among the three banks,
which contributed to the inadequate business practice. Mizuho planned to restructure the organization
after reviewing the administrative structure as well as the development scheme of the unified banking
system.
(3) The three banks decided not to independently prepare and develop banking systems prior to integration,
which le ad to a n ab sence of e xchanging d evelopment s tatus am ong t hree b anks an d c ontributed t osystem failures. The new dev elopment scheme encouraged c ooperation of the en gineers of the thr eebanks to jointly develop the integrated banking system.
6. Summary
Although the co nsolidation of th e tree banks created the world’s largest bank by assets and integrating the6

Failure Knowledge Database / 100 Selected Cases
three banks’ systems required en ormous t asks, t his incident r evealed poor cor porate management andexcessive optimism over t he new business and the mission-critical system integration, which may also be
observed a cross industries. It is c ritical fo r b anking business t o b uild a f ault-free c omputer s ystem. In
particular, fault -free banking information and accoun t systems are mission-critical to th e bank. It is
unavoidable for an y m erger o f banks to un ify su ch mission-critical sy stems. Mizu ho g roup had been
preparing for the s cheduled sy stem integration on A pril 1, 2002 s ince the previous y ear; ho wever, theunified ban king sy stem wa s de veloped through a trial an d er ror process to whi ch the cause o f sy stem
failures was attributed.
The management committee of the new banks multiplied in number after merger by keeping all membersof the thr ee banks, a pr actice commonly obs erved in any mer gers. W ithout ha ving the dominating par tythat can ef fectively take charge, all administrative decisions required unanimous agreem ent of the threebanks. Rivalry an d p ower str uggle a mong t he t hree banks r esulted in delayed de cision o n the system
integration s cheme an d o ne-year pos tponement of the or iginal in tegration p lan. This del ay ended up
leaving insufficient time for perfor mance testing of bridging systems, data preparation and load testing forthe large-scale o peration. While t hree banks h ad evident d elay in pr eparation f or th e sy stem i ntegration,
they we re t oo fix ated on th eir sched ule in April to allow th e M izuho Ho lding m anagement co mmittee
making approp riate judgm ents o n th e d elay. Corpo rative facto rs in cluding p oor management andcommunication greatly contributed to the incident. Mizuho group bears heavy responsibility as the banking
group that caused general chaos involving thousands transaction errors and delayed debits.
This incident caused immeasurable damage to the society and showed problems of the information society.
It also p roved how much ben efit th e Japan ese eco nomy receives fr om infor mation t echnology (IT) an dmade one re affirm th e significa nce of it in the socie ty. S ystem failures ha ve also be en rep orted in th e
finance and the aviation ind ustries. The pressing n eed f or th orough in spection and maintenance of
information systems are obvious.
Since this incident led to potential crisis of confidence in the Japanese financial sy stem and the financial
administration, J apan nee ds to emphasize significance of infor mation sy stems and encourage inves tment
and education to the IT industry as well as to the organizations that utilize the technology.
7. Knowledge(1) System failures generally occur on the systems that bridge external systems to the mainframe.
(2) Systems r equire thorough test s incl uding con nection, st ress tes ts, enh ancement t ests, and fault
tolerance before bringing them into the real operation.
(3) A system design requires a clear architecture concept to begin with.
(4) Integration of sy stems for merger requires detailed review of the existing systems to propose the mostrational approach and scheme.
(5) The administration executives must have better understandings on the significance of mission-critical
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Failure Knowledge Database / 100 Selected Cases
systems for business operations.
(6) Reorganization and r ationalization of the executive ma nagement is essential for succ essful corporate
merger. It i s i rrational in b usiness perspective to keep all execu tives and em ployees or to form t he
management committee with the same number of executives from companies involved in the merger.
8. BackgroundStarting with the Bank of Tokyo-Mitsubishi UFJ, there had been a series of incidents of system failures atfinancial institutions such as Mizuho Bank, Post Office Savings Bank and IY Bank (current Seven Bank,Ltd.). The sy stem fa ilures surfaced t o be AT M tr ansaction er rors r esulted fr om pr oblems in the br idge
connection between banking network systems and the mainframe.
There we re also social f actors tha t contributed to these in cidents: di versification of s ervices a nd r adical
reorganizations in the finance industry observed in the recent years. Merger of banks as we have seen in the
Bank of Tokyo-Mitsubishi UFJ and Mizuho Bank requires sig nificant revisions of banking systems. Suchbanking systems must also offer capabilities of debit transactions and networking with Post Office Savings
Bank and credit unions, which significantly increase the system load.
Electronic transactions offer direct business between sellers and buyers without an intervening party. Suchtransactions r equire a h igh availability tr ansaction processing s olution commonly develop ed o n an op en
system env ironment, r ather tha n on a l egacy sy stem en vironment. While suc h a solu tion o ffers highavailability and consistent, short response times to enable online real-time processing of mas s transaction
data, it requires relatively complex network architecture. Many corporations and manufacturers now facedifficulties in catching up with e-commerce trends and implementing new transaction solutions.
Unquestioning belief in infor mation sy stems is an other pr oblematic fa ctor observed co mmonly ingovernment agencies and industries in Japan. Unlike the quick economic recovery of the IT industry in the
U.S., declining stock prices of many IT companies in Japan has been putting a damper on already faltering
investment s ince th e co llapse of the asset-inflated e conomy in 1990’s. Many IT c ompanies a re still
struggling with slu ggish co rporate gr owth with out being ab le to al leviate t heir sta ffing sho rtage. Whi lemany companies brought new IT technologies to their work environment, an inadequate employee training
is pr eventing the m to take ful l adv antage o f their upd ated in formation systems. So me of the leading
manufacturers recen tly announced large layoffs o f more th an 90,000 em ployees; ho wever, most of thelayoffs are targeting those who jo ined the co mpanies th rough th e mass h iring d uring t he boo m of home
appliances, not the ones wh o join ed th em after the comin g of age of th e Internet. This als o proves tha t
corporations hav e a serio us shortageof em ployees wh o a re fa miliar w ith the re cent i nformation

technologies.
9. On the Side
Expanding a system simply by adding capabilities to the existing one can go just so far until it creates load
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Failure Knowledge Database / 100 Selected Cases
imbalance or processing i nefficiency. The system i ntegration in this c ase f ailed due to t he networkarchitecture shown in Figure 2. The bank should have created a new banking network as shown in Figure 3
after assessing requirements and restrictions of the new banking system.

Figure 2. Adopted System Integration Scheme

Figure 3. Desirable System Integration Scheme
References[1]“Mizuho A TM Sy oogai-no Gen-in, S etsuzoku Computer-no Fu-Guai ( Network Bridge Failu res Ca use
Mizuho ATM Transaction Errors)”, April 1, 2002, The Asahi Shinbun.

[2]“Mizuho-o Tachi-Iri Kensa, FSA-ga Go-Gatsu Joojun-ni Jisshi (FSA to Inspect Mizuho in Early May)”,
April 19, 2002, The Yomiuri Shimbun.

[3]“Kensyo, Miz uho Sy stem Sy oogai, Ni nshiki Ama- ku, Doro Nu

ma-ni T otsu-Nyuu (Mizuho’s

Underestimation of System Failures Causes Chaos)”, April 20, 2002, The Yomiuri Shimbun.
[4]“Mizuho, Toogo o Mae-ni Kek kan Haaku (Mizu ho K new Err ors before In tegration)”, April 23, 2 002,
The Sankei Shimbun.

[5]“Mizuho S hachoo, Sy uuin-I-de Keiei Seki ni-wa Ke nsa Go-ni ( Summoned Mizu ho P resident to Res ign
9Failure Knowledge Database / 100 Selected Cases
after Inspection)”, April 24, 2002, The Yomiuri Shimbun.
[6]“Kensyo, Mizuh o T rouble, Do tamba-de Hooshin Hen koo, K onran Kakudai (Last M inute Chan ge in
Integration Scheme Confused Engineers)”, April 24, 2002, The Asahi Shinbun.

[7]“Mizuho Shacyoo, Syoogai-no Zenyoo Tsuka-me-zu (Entire Picture of the Incident Unknown to Mizuho
President) – 4 Dai K inyuu Sy unoo, Syuuin-I Syookan, Te st Fujy uubun (4 Bank Heads Testified
Inadequate System Testing before Congress)”, April 24, 2002, Nihon Keizai Shimbun.

[8]“Mizuho Fuk ugoo Miss, Kon ran Z oofuku, Kensy o, System Sy oogai, Ko oza Furikae, Tenken Ama-ku(Mizuho Sy stem In tegration Failure Caus es Chaos, Inadeq uate Testing Re sulted i n T ransaction Err ors
and System Failures)”, April 23, 2002, Nihon Keizai Shimbun.

[9]“System Toogoo, Kinyuu Saihen-ni Omoi Risk, Mizuho Syoogai Chinseika (System Integration Risky to
Bank Merger, Mizuho Chaos Calmed Down)”, May 01, 2002, Nihon Keizai Shimbun.

[10] “Jizen T est Fujyuubun Datta, Mizuho Maeda Shacyoo-ga Sy uuin-I-de ( Summoned Maeda President ofMizuho Testified Insufficient System Testing before Congress)”, April 24, 2002, The Asahi Shinbun.
[11] “Mizuho-ga Saisyuusyo, Yoo ka Kara Tachi-Iri Ke nsa (Mizuho S ubmitted F inal Report, Insp ection
Begins on 8th)”, May 07, 2002, The Asahi Shinbun.
[12] “Yomiuri Shase tsu 1 ( Yomiuri Editorial 1 ), Mi zuho H ookoku, S hinrai Kaifuku-he-no Michi-wa Mada
Mewashii (Mizuho Rep ort, S truggle to Res tore Customers’ Trust)”, May

08, 2002, T he Y omiuri

Shimbun.
[13] “Mizuho Group-ni Tachi-Iri Kensa, FSA, BOJ (FSA and BOJ Inspect Mizuho Group on Site)”, May 08,
2002, The Asahi Shinbun.
[14] “Mizuho-ga Akiraka-ni Shi ta – TAITO G APPEI, K ore-dake-no A yamachi (Mizuho R evealed, Equal
Merger a Mistake)”, May 12, 2002, Nihon Keizai Shimbun.
[15] “Mizuho Ginko: B u Shitencyo Kaigi-o Kaisai, Jinji Minaoshi-de Keiei Kaikaku (Mizuho Bank: BranchManagers Meeting Di scussed Reorganization andRestructuring)”, M ay 1 9, 2 002, Th e Main ichi

Newspapers.
[16] “Mizuho, Saisei-e Koodoo Keikaku, Roku Gatsu Medo-ni Sakutei (Mizuho to Complete Reform Plan inJune)”, May 22, 2002, The Yomiuri Shimbun.
[17] “Syoogai-kara Ni Kagetsu – Mi zuho, Saisei P lan Isogu (2 Months after the Incident, M izuho Rushes
Reform Plan)”, June 02, 2002, The Yomiuri Shimbun.
[18] “System Shoogai, Mizuho Kensa Syuuryoo, FSA to Issue Business Improvement Order)”, June 06, 2002,
Nihon Keizai Shimbun.
[19] “System Shoogai, Mizuho

Keiei-jin N inshiki A maku –Shacyoo, Syuin-I-de H yoomei (Mizuh oManagement Underestimated System Failures, Summoned Mizuho President Testified before Congress)”,
June 12, 2002, Nihon Keizai Shimbun.
[20] “Mizuho S hacyoo, San-gyoo A tsureki Hansei, Sy stem S yoogai, Tasukigake Jinj i H aishi (Mizuho
President Regrets 3 Bank’s Powe r Struggle that Caused S ystem Failures, M izuho to P ush t hrough10Failure Knowledge Database / 100 Selected Cases
Reorganization)”, June 13, 2002, Nihon Keizai Shimbun.
[21] “Jibun-o Mamoru Kiki Kanri Jyutu (Risk Management for Saving Yourself)”, Nikkei Business Associé,July 2002, Vol. 3, Nikkei Business Publications Inc., 24-26.
[22] “Dai-Shippai-no Mechan ism, San-no Bais uu-no Ronr i (Mechanism o f Cat astrophe, Theory of Three
Multiples)”, President, July 1, 2002, 88-93.
[23] “Mizuho Gin, Teimei-no Nisyuukan-o Ou (Doomed 2 Weeks at Mizuho Bank)”, Nikkei Computer, April
22, 2002, 12-15.
[24] “Scoop – Mizuho G inkoo-no Sy stem Syoogai, Sh insoo-ga H anmei, Taigai Setuzo ku-kei-no S yuusei-oMiss, Furikae Mad e (News Fla sh: Mizuho Ba nk’s Sys tem Fa ilures Revealed, Bug in Network Bridge
Program Interrupted Debits)”, Nikkei Computer, May 06, 2002, 11.
[25] “Joohoo System-no Kiki Kanri-o Mi nao-se (R eviewing Pl an o f Risk Management fo r Information
Systems)”, Nikkei Computer, June 03, 2002, 154-160.

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