
ãå調ä»å ¥ã®æŽå²ã𿥵ããŠæå¹ãªåœ±é¿ðããJapanese Foreign Exchange Interventions, 1971-2018:Estimating a Reaction Function Using the Best ProxyãïŒå è¡ç 究解説 No.15ð2023/11/04
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ãJapanese Foreign Exchange Interventions, 1971-2018: Estimating a Reaction Function Using the Best Proxyã
Takatoshi Ito(a), Tomoyoshi Yabu(b)
(a) School of International and Public Affairs, Columbia University, and GRIPS, Tokyo
(b) Department of Business and Commerce, Keio University
Japanese Foreign Exchange Interventions, 1971-2018: Estimating a Reaction Function Using the Best ProxyÂ
December 12, 2019
Takatoshi Ito(a), Tomoyoshi Yabu(b)
(a) School of International and Public Affairs, Columbia University, and GRIPS, Tokyo
(b) Department of Business and Commerce, Keio University
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6. International Coordination or non-Coordination

6.1. Policy coordination on exchange rates
The Group of Seven (G7) monetary authorities were engaged in interventions very frequently during the 1970s and 1980s. However, the frequency of interventions declined during the 1990s.
Frequent interventions by the US, Germany and the UK ceased by 1995.
The frequency of Japanese intervention also declined after 1995, apart from 14 months of frequent interventions from January 2003 to March 2004.
äž»èŠïŒã«åœ(G7)éèåœå±ã¯ã1970幎代ãã1980幎代ã«ãããŠéåžžã«é »ç¹ã«ä»å
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During the period of frequent interventions, there were many cases where two or three of the G3âthe US, Japan and Germanyâintervened in the same direction simultaneously.
There were also cases of US-Japan joint interventions; US-German joint interventions and even three-way interventions.
When engaging in joint interventions, they must have shared the same views in terms of the level and movement of the exchange rate, such as the idea that since the US dollar is overvalued, the US should buy German marks and Japanese yen, while Germany and Japan should sell US dollars.
When two or three authorities intervene in the same direction in the same month, we refer to them as âcoordinated interventionsâ throughout the rest of the paper.
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Fig. 6 shows that the number of months per year during which the authorities coordinated their interventions from 1976 to 1995.
For example, in 1979, US-German joint interventions were conducted during nine months and US-German-Japanese joint interventions were conducted during three months.
In September 2000, there was a joint ECB-US-Japan intervention in order to stop further depreciation of the euro.
On March 18, 2011, the G7 countries intervened to reverse the direction of yen appreciation that had progressed following the Great East Japan Earthquake.
One of the proposed reasons for this appreciation was based on speculation that Japanese insurance companies would need to liquidate assets abroad and convert them to yen to pay for claims. (See Neely 2011).
The aforementioned coordinated intervention, the first since 2000, played a crucial role in stabilizing the yen.
Policy coordination on exchange rates among the G5 countries occasionally had dramatic effects during the 1970s and 1980s.
The most prominent example of this was the period bookended by the Plaza agreement of September 1985 and the Louvre accord of February 1987.

å³6ã¯ã1976幎ãã1995幎ãŸã§é貚åœå±ãä»å
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2000幎以æ¥åãšãªãåè¿°ã®ãå髿¯æ£ãç®çãšããå調ä»å
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6.2. Case Study: Policy coordination under the Plaza and Louvre agreements
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çµæžç ç©¶ãVol.54 No.2 Apr. 2003
ãEffects of the Bank of Japanâs intervention on yen/dollar exchange rate volatilityã21 November 2004
Toshiaki Watanabe (a), Kimie Harada (b)
ãThe Effects of Japanese Foreign Exchange Intervention: GARCH Estimation and Change Point Detectionã
Eric Hillebrand Gunther Schnabl Discussion
Paper No.6 October 2003
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