可能会影响将来的走势 但是不会影响当前的价值 以下是从wiki拷贝过来的 Index maintenance[edit] In order to keep the S&P 500 Index consistent over time, it is adjusted to c apture corporate actions which affect market capitalization, such as additio nal share issuance, dividends and restructuring events such as mergers or sp in-offs. Additionally, to remain indicative of the U.S. stock market, the co nstituent stocks are changed from time to time.[3] To prevent the value of the Index from changing merely as a result of corpor ate financial actions, all such actions affecting the market value of the In dex require a divisor adjustment. Also, when a company is dropped and replac ed by another with a different market capitalization, the divisor needs to b e adjusted in such a way that the value of the S&P 500 Index remains constan t. All divisor adjustments are made after the close of trading and after the calculation of the closing value of the S&P 500 Index. There is a large ran ge of different corporate actions that can require the divisor to be adjuste d. These are listed in the table below:[18] Type of Action Divisor Adjustment Stock split (e.g. 2×1) No Share issuance Yes Share repurchase Yes Special cash dividend Yes Company change Yes ? ? Rights offering Yes Spinoffs Yes Mergers Yes
【在 s***m 的大作中提到】 : 可能会影响将来的走势 : 但是不会影响当前的价值 : 以下是从wiki拷贝过来的 : Index maintenance[edit] : In order to keep the S&P 500 Index consistent over time, it is adjusted to c : apture corporate actions which affect market capitalization, such as additio : nal share issuance, dividends and restructuring events such as mergers or sp : in-offs. Additionally, to remain indicative of the U.S. stock market, the co : nstituent stocks are changed from time to time.[3] : To prevent the value of the Index from changing merely as a result of corpor