我國公司上市櫃前後績效之研究

Abstract

本研究以1994年至2005年1340多家上市櫃之公司為研究對象，探討其首度上市櫃後在資產報酬率、營業毛利率以及稅前淨利率等指標中是否有惡化的現象。 本研究首先以Wilcoxon Signed-rank test做檢定，結果顯示上市櫃公司在上市櫃後績效表現明顯變差。接著採用動態因子分析(Dynamic Factor Analysis)，分析變數的共同趨勢(Common Trend )，結果顯示大部分的產業在上市櫃後的績效表現皆有惡化的現象。而分析台灣十大產業內公司之共同趨勢更進一步發現營建業、通訊業以及網路設備等產業績效惡化情形最為嚴重。

The paper studies the operating performance of more than 1340 IPO firms in Taiwan from 1994 through 2005. The paper investigates the change in operating performance of firms as they make the transition from private to public ownership. We examine whether the operating performance of 1340 IPO firms in Taiwan from 1994 through 2005 deteriorated. First, by using Wilcoxon signed rank test, we find significant decline in operating performance subsequent to the initial public offering (IPO). Second, by using dynamic factor analysis, we find that IPO firms deteriorate after going public especially in construction, communication, and network modem industry. Using ten industries as variables, it becomes clear that the three measures of return on assets, gross margin, and earnings before tax margin have the tendency to perform better before going public then perform worse after going public.