At present, the most concerned "40 1K" plan in China is only a branch of the employer pension plan. Since the implementation of 198 1, the "40 1K" plan has grown rapidly. Encouraged by the tax incentives for pension investment, more than 1/4 of the total population of the United States participated in the plan. Enterprises set up a special "40 1K account" for employees, and employees pay a certain percentage of their wages into the account every month, and enterprises also pay corresponding funds into the account according to a certain percentage (not exceeding the amount paid by employees). The funds in these accounts are invested by third-party professional institutional investors, and the investment varieties can be financial products such as stocks, funds, annuity insurance, bonds and special time deposits. In the asset allocation of 40 1k plan, equity funds account for the largest proportion. In 2009, 4 1% of the planned assets were invested in stock funds, 9% in stocks, 45% in its balanced or partial debt funds, and only 5% in the money fund, so private pensions are the most important institutional investors in the US capital market.