為探討經濟政策不確定性與公司租稅規避行為之間的關聯性，本文以2013年至2021年臺灣上市上櫃公司資料為研究樣本，實證結果顯示，全球EPU指數與公司現金有效稅率呈現負向關聯，代表在面對經濟政策不確定性增加時，公司基於預防性動機考量，以更積極的租稅規避行為減少現金流出，作為日常營運及因應未來投資機會所需。惟依據穩健性測試結果，該項負向關聯性仍隨樣本期間、公司規模、產業類別等因素而有變化及顯著程度差異。本文額外發現，資產報酬率愈高、市值對帳面價值比愈高及屬高科技產業的公司，在面對經濟政策不確定時所採取租稅規避的程度較輕微，顯示公司獲利能力、成長機會及產業屬性等因素，對該項負向關聯具調節效果。

This paper investigates the link between economic policy uncertainty and corporate tax avoidance. The study finds empirical evidence about a negative relation between economic uncertainty policy and cash effective tax rate, as a proxy variable of corporate tax avoidance, among listed and over-the-counter firms in Taiwan from 2013 to 2021. Furthermore, the study finds moderating effects of firm-level factors such as ROA (return of assets), MTB (market to book value ratio) and high-tech industry lighten the abovementioned relation. The study suggests that economic policy uncertainty induces precautionary motives of corporate tax avoidance. However, based on results of sensitivity analysis, that relation between economic policy uncertainty and corporate tax avoidance is not robust in different sample period, large firm size samples, and over-the-counter company samples.

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