IDEAS home Printed from
   My bibliography  Save this paper

Moody’s credit ratings and the stock market performance of Portuguese rated firms


  • Pacheco, Luís


Never has the issue of sovereign credit ratings attracted such an interest by policy and opinion makers, bankers and journalists, or even the public opinion, as witnessed in the last couple of years. In spite of being accused of contributing to the instability of financial markets, credit rating agencies have undoubtedly a role in financial markets, affecting its performance and guiding investor’s decisions. This paper analyzes the impact of the announcement of changes in Moody’s ratings over the performance of a set of rated firms quoted in the Portuguese stock market. Following an event study methodology, we collect ratings and outlook announcements by that major credit agency over the period 2006-2011. We find a significant response of share prices to changes in ratings, with that response anticipating the announcement. We think that could be explained by previous sovereign rating changes or to the contagion effects of a bearish market. When analyzing the period after January 2010, we observe a stronger reaction to announcements, which is understandable given the greater influence and market sensitivity to rating agencies.

Suggested Citation

  • Pacheco, Luís, 2011. "Moody’s credit ratings and the stock market performance of Portuguese rated firms," MPRA Paper 36551, University Library of Munich, Germany.
  • Handle: RePEc:pra:mprapa:36551

    Download full text from publisher

    File URL:
    File Function: original version
    Download Restriction: no

    Other versions of this item:

    References listed on IDEAS

    1. Bertrand Candelon & Amadou N Sy & Rabah Arezki, 2011. "Sovereign Rating News and Financial Markets Spillovers; Evidence from the European Debt Crisis," IMF Working Papers 11/68, International Monetary Fund.
    2. Joo, Sang Lyong & Pruitt, Stephen W., 2006. "Corporate bond ratings changes and economic instability: Evidence from the Korean financial crisis," Economics Letters, Elsevier, vol. 90(1), pages 12-20, January.
    3. Afonso, António & Furceri, Davide & Gomes, Pedro, 2012. "Sovereign credit ratings and financial markets linkages: Application to European data," Journal of International Money and Finance, Elsevier, vol. 31(3), pages 606-638.
    4. Brooks, Robert & Faff, Robert W. & Hillier, David & Hillier, Joseph, 2004. "The national market impact of sovereign rating changes," Journal of Banking & Finance, Elsevier, vol. 28(1), pages 233-250, January.
    5. Carmen M. Reinhart, 2002. "An Introduction," World Bank Economic Review, World Bank Group, vol. 16(2), pages 149-150, August.
    6. Gande, Amar & Parsley, David C., 2005. "News spillovers in the sovereign debt market," Journal of Financial Economics, Elsevier, vol. 75(3), pages 691-734, March.
    7. Reisen, Helmut & von Maltzan, Julia, 1999. "Boom and Bust and Sovereign Ratings," International Finance, Wiley Blackwell, vol. 2(2), pages 273-293, July.
    8. Brown, Stephen J. & Warner, Jerold B., 1980. "Measuring security price performance," Journal of Financial Economics, Elsevier, vol. 8(3), pages 205-258, September.
    9. Lawrence J. White, 2010. "Markets: The Credit Rating Agencies," Journal of Economic Perspectives, American Economic Association, vol. 24(2), pages 211-226, Spring.
    10. Mora, Nada, 2006. "Sovereign credit ratings: Guilty beyond reasonable doubt?," Journal of Banking & Finance, Elsevier, vol. 30(7), pages 2041-2062, July.
    Full references (including those not matched with items on IDEAS)


    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.

    Cited by:

    1. repec:wsi:gcrxxx:v:05:y:2015:i:01:n:s2010493615500087 is not listed on IDEAS
    2. Lucian Ivan, Dragos, 2012. "The Double Articulation of the Welfare-State: A demographic drop of jeopardy?," Working Papers 25/2012, Universidade Portucalense, Centro de Investigação em Gestão e Economia (CIGE).

    More about this item


    Credit Rating Agencies; Event Studies; Stock Market; Moody’s; Sovereign Debt Crisis; Portugal;

    JEL classification:

    • G14 - Financial Economics - - General Financial Markets - - - Information and Market Efficiency; Event Studies; Insider Trading
    • E44 - Macroeconomics and Monetary Economics - - Money and Interest Rates - - - Financial Markets and the Macroeconomy
    • G10 - Financial Economics - - General Financial Markets - - - General (includes Measurement and Data)
    • G24 - Financial Economics - - Financial Institutions and Services - - - Investment Banking; Venture Capital; Brokerage

    NEP fields

    This paper has been announced in the following NEP Reports:


    Access and download statistics


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:pra:mprapa:36551. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Joachim Winter) or (Rebekah McClure). General contact details of provider: .

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.