什么情形适合定投ETF？

Group 1 - The core concept of fund regular investment (定投) is to invest a fixed amount in a designated open-end fund at regular intervals, similar to a bank's zero-deposit savings method [1] - Fund regular investment helps to mitigate the risks associated with market timing by allowing investors to accumulate shares at lower costs during market downturns, thus enhancing potential returns when the market rebounds [1] - The strategy is particularly effective in volatile markets, where higher volatility and growth potential indices yield better returns when sold during a bull market [1] Group 2 - For ordinary retail investors, regular investment can be achieved through investing in ETFs or ETF-linked funds, with some brokerage systems now supporting ETF regular investment [2] - ETF-linked funds typically have different share classes, where A shares are suitable for long-term investment due to their one-time subscription fee and no sales service fee, while C shares are more appropriate for short-term investment due to their sales service fee structure [2] - Investors are advised to choose off-market A shares for regular investment to optimize their investment strategy [2]