本研究旨在探討一年期定期定額投資策略之時點選擇是否影響其投資績效,研究區間為2011年1月1日至2021年12月31日,共11年資料。研究樣本為台灣10家指數股票型基金ETF價格日資料,研究方法為OLS最小平方法。 實證結果顯示:一年期定期定額投資策略之投資時點選擇對投資績效有影響且其影響方式於2018年前後存在結構性改變。 This study aims to explore whether the investment timing selection of one-year regular fixed investment strategy affects its investment performance. The study period spans from January 1, 2011, to December 31, 2021, covering the datas of 11 years. The research sample consists of daily price data from 10 Taiwan index stock ETFs. The research methodology employed is the Ordinary Least Squares (OLS) method. The empirical results show that: the choice of investment timing of the one-year regular fixed investment strategy has an impact on its investment performance, and the impact method has structural changes around 2018.