公營企業民營化對公司股價及經營績效之影響

The Impact of Stock Price and Operating Performance After Privatization of Government-Owned Enterprises

陳鴻銘(Hung-Ming Chen)

指導教授 ： 李瓊映

長榮大學/管理學院/經營管理研究所(博)/碩士(2008年)

摘要

公營事業在台灣的經濟發展中扮演著舉足輕重的角色，然近年來隨著時代的變遷與經濟結構的轉變，部分公營事業機構之經營面臨前所未有的衝擊，公營企業走向民營化勢在必行，其為政府既定財經政策之一。自民國78年起，我國公營事業紛紛透過釋股，移轉成民營企業。
過去有關民營化之相關研究甚多，然討論的議題多為比較民營化後企業經營績效是否提昇；抑或比較公營與民營企業的經營績效，孰者為佳。對於有關民營化過程中，釋股對股價的影響則著墨不多。故本研究嘗試以事件研究法之市場模型來探討公營事業於民營化過程中，釋股日前後股價之變化，以瞭解民營化後對股東之報酬是否有顯著不同。再以股東權益報酬率、純益率、總資產報酬率為獲利能力指標；以資產週轉率為經營能力指標；以權益乘數為償債能力指標來衡量經營績效。
實證結果顯示，在股價方面，釋股日前三天到前一天股價確有顯著的正向累積異常報酬，釋股日後則不顯著。此結果表示，因公司釋股日已提前公告所以釋股日前投資人已先買入該公司股票，股價提前反應。因此日後若投資者對此類股票有興趣，應斟酌注意此現象。在經營績效方面，股東權益報酬率、純益率及總資產報酬率在民營化後皆有上升，權益乘數與總資產週轉率在民營化後呈下降趨勢，故民營化後樣本公司運用資產的效率不彰。

關鍵字

民營化 ； 事件研究法 ； 累積平均異常報酬 ； 經營績效

並列摘要

The government-owned enterprises play an important role in the economic development of Taiwan. In recent years, the management of certain of government -owned enterprises face the unprecedented impacts. One of government’s financial and economic policies is let government-owned enterprises toward privatization. Since nineteen eighty nine, government-owned enterprises had transferred to privatization by release.
In the past, there were a lot of relevant researches about privatization. Most subjects were compared the performance of enterprises which advance or not after privatization or compared the performance of enterprises which one is better between government-owned and privatize. Less for effect of stock prices after released shares in privatization process. In order to understand the different of returns of equity after privatization, the purpose of this study is to confer the change of stock prices before and after released shares in the privatization process of government-owned enterprises with event study. To measure operating performance, this research use the return on equity、return on sales and return on assets as indexes of profitability; the assets turnover as index of ability of operating performance and the total assets to equity as index of debt-paying ability.
This study results show that there were significant positive cumulative abnormal returns before three to one days of released shares. This result is express the investors have bought stocks in advance before released shares because the days of companies’ released shares have announced in advance. If there were investors interested in these stocks in the future, be careful of this phenomenon. In the operating performance, the ratios of return on equity, return on sales and return on assets are raised after privatization. The total assets to equity and the assets turnover have trends of down after privatization. In these samples the efficiency of the assets is not well after privatization.

並列關鍵字

privatization ； event study ； cumulative average abnormal returns

參考文獻

8.張琬喻（2004）。台灣企業宣告從事電子商務對股東財富的影響。台灣管理學刊，第4卷，第2期，頁161-186。

7.林銘鈺（2003）。台灣地區公營銀行民營化經營效率之研究-DEA方法之應用。成功大學企業管理學系碩士論文。

2.王藝蓉（2003）。金融控股公司設立對股東財富之影響。成功大學財務金融研究所碩士論文。

1.Boubakri, N. & Cossert, J. C. (1998). The Financial and Operating Performance of Newly Privatized Firms: Evidence from Developing Countries. Journal of Finance(June), 53(3), pp. 1659-1679.

2.Bowman, R. G. (1983). Understanding and conducting event studies. Journal of Business Finance of Accounting, 10, pp.561-84.