市場利率持續走低的情況下，本研究提出以債券指數替代銀行利率的「配置型定期定額策略」，即期初將資金全數放在債券指數型基金，每月由債券指數型基金定額贖回投資到股票指數型基金，配置型定期定額方式比傳統方式更能風險分散及獲得債券指數穩定報酬之效益。為避免投資人選股及擇時兩大問題，本研究分別就單筆投資、傳統型與配置型定期定額不同方式投資指數型基金策略進行探討，並進一步檢視定期定額策略在投資期間有無停利損績效之差異。實證結果發現，債券指數持續成長使得單筆投資債券指數的年化報酬率穩定在6%以上，優於單筆存放於銀行或單筆投資台股指數。配置型定期定額策略無論停利損與否，其平均年化報酬率皆顯著大於傳統策略。配置型定期定額設停利損績效顯著優於無停利損績效，其中以停利20%年化報酬率最高，投資期間三年以上其年化報酬率亦能顯著優於單筆投資債券指數。配置型定期定額同時停利停損10%策略的風險最小、風險調整後績效（Sharpe比率及Sortino比率）最佳。投資期間愈長，配置型定期定額停利損之績效提升效果愈明顯。因此，本研究提出「配置」及適時執行「停利損」是長期投資人提升定期定額投資績效不可或缺的兩個重要因素。

Since interest rates are on the decline, this study shows that the dollar-cost-averaging (DCA) allocation strategy (that is the initial principal to be invested in the bond index fund and investors redeem mutual fund each month from bond index fund to stock index fund) can diversify the portfolio risk better and has more stable return than the traditional approach. To avoid the selectivity and timing issue, this study examines primarily the lump sum strategy (LS), allocation DCA strategy, and the traditional DCA approach for the index mutual funds. We also examine the performance by incorporating the take-profit (stop-loss) approach during the investment periods. The results show that the increasing trend of bond index makes the average annualized return of lump-sum strategy in bond index fund above 6%, which performs better than funds in bank deposits or the lump-sum strategy in the stock index fund. Regardless of take-profit (stop-loss), the average annualized return of the allocation DCA strategy significantly outperforms than traditional DCA strategy. The allocation DCA strategies with take-profit (stop-loss) are better than without take-profit (stop-loss) strategy. The annualized return is the highest if the allocation DCA strategy sets up the take-profit at the 20% level, and the performance can even surpass the lump-sum for bond index fund in annualized return if investment period is longer than three years. The risk is smallest and the risk-adjusted performance (Sharpe ratio and Sortino ratio) is best if the strategy sets up take-profit and stop-loss at the 10% level. The performance improvements for allocation DCA strategy with take-profit (stop-loss) are more apparent for longer investment horizon. In other words, our study suggests that ＂allocation＂ and ＂take-profit (stop-loss)＂ are two important factors for long-term investors to increase their performance of dollar cost averaging.