2. As the name implies, index funds are fund products with specific indexes (such as Shanghai and Shenzhen 300 Index, Standard & Poor's 500 Index, Nasdaq 100 Index, Nikkei 225 Index, etc.) as the target. ) as the target index, and take the constituent stocks of the index as the investment object, build a portfolio by buying all or part of the constituent stocks of the index, and track the performance of the target index. Generally speaking, the index fund aims to reduce the tracking error, make the change trend of the portfolio consistent with the underlying index, and thus obtain roughly the same rate of return as the underlying index.