貨幣高估或低估取決於均衡匯率與名目匯率間之相對變化。本文以考慮Balassa-Samuelson 效果之貨幣學派模型, 重新探討台灣1980年以來的匯率制度與政策,分析匯率干預是否有助於匯率穩定與經濟成長, 及探討央行匯率干預的利潤與損失。實證結果指出央行在1980:12–1987:05之期間採新台幣阻升政策, 在1987:06–1997:11之期間採阻貶政策, 然在1997:12–2010:06之後亞洲金融危機期間則採維持匯率均衡穩定政策。新台幣阻升政策使名目匯率波動加劇, 使央行蒙受巨額之干預損失, 然阻升政策有助於經濟成長。在後亞洲金融風暴期間(1997:12–2010:06)及全樣本期間下, 匯率干預大致縮小名目匯率波動,且央行在此二時期之干預利潤為正。

The undervaluation or overvaluation of domestic currency depends on the
relative movement of the nominal exchange rate and its equilibrium rate.
This paper adopts a monetary model with Balassa-Samuelson effects to investigate Taiwan’s exchange rate policies since 1980. Specifically, we examine if the central bank adopts different exchange rate policies during different sub-periods, analyze if intervention stabilizes the nominal exchange rate and promotes economic growth, and discuss the profitability of intervention.
Empirical results show that the central bank adopted devaluation policies
during the period of 1980:12–1987:05, revaluation policies over the period of 1987:06–1997:11, and exchange ate stabilization policies during the post Asian financial crisis period, 1997:12–2010:06. The devaluation policy over 1980:12–1987:05 increased nominal exchange rate volatility and resulted in significant unrealized loss, but it promoted economic growth. In addition, during the period atter the Asian financial crisis (1997:12–2010:06) and over the whole period, official intervention tended to stabilize nominal exchange rates and led to significant profits.