衡量與分解臺灣銀行業生產力與利潤力變動

Measuring and Decomposing the Taiwanese Banking Productivity and Profitability Change

過去研究多使用Malmqusit總要素生產力(total factor productivity, TFP)指數來衡量廠商生產力變化，然而此指數是一局部生產技術指數，用於生產力估計可能產生偏誤。為彌補此缺點，本文應用符合傳統生產力指數定義之Hicks-Moorsteen TFP指數探討臺灣銀行業生產力變動。同時，此指數與交易條件指數的乘積為利潤力指數， 有助於我們深入了解交易條件的改變如何影響廠商生產決策。實證研究顯示2005年至2012年臺灣本國銀行業交易條件持續惡化，TFP則較常出現改善狀況，但利潤力則衰退居多，因此交易條件大致左右了利潤力的變動。樣本期間，TFP顯著成長，而TFP之變動，長期主要來自技術進步，短期則亦與純技術效率、產出組合效率與規模效率變動密切相關，2008年全球金融海嘯影響生產力與利潤力表現甚巨。本文亦發現在生產力指數與技術變動上，金控銀行表現優於獨立銀行。最後，統計檢定結果顯示Hicks-Moorsteen TFP指數及Malmquist TFP指數具有顯著的差異性。

A number of more recent studies on banking performance employ the Malmquist TFP index to explore productivity change, but this index is a local technology index, thus resulting in productivity estimates potentially being biased. To remedy the existing shortcoming, this paper adopts the multiplicatively-complete Hicks-Moorsteen TFP index to investigate the domestic banking productivity change in Taiwan. The property that the product of the H-M productivity index and the terms of trade index equals the profitability index is very helpful for understanding how terms of trade change and affect a firm’s production decision. Empirical research shows that from 2005 to 2012, Taiwan’s domestic banking terms of trade continued to deteriorate, productivity was more prone to improve, but profitability often showed a decreasing trend, and therefore the change in terms of trade generally was dominating profitability. During the sample period, TFP grew notably. While TFP change in the long term was mainly from technological progress, change in the short term was closely associated with pure technical efficiency, output mix efficiency, and scale efficiency. The 2008 global financial tsunami severely affected the performance of the Taiwanese domestic banks. This paper also finds that financial holding banks outperformed independent banks in both TFP change and technological change. Finally, the statistical test shows significant differences between the Hicks-Moorsteen TFP index and the Malmquist TFP index.