In quantitative investment, the length of time a company has been listed is considered an important indicator for measuring the maturity and information transparency of a company. Generally speaking, companies that have been listed for a longer time usually have more stable business models and operating conditions, and their financial information is more transparent, so they are considered to have a lower risk premium. However, it should be noted that companies that have been listed for too long may also face the challenge of slowing growth. Therefore, this factor needs to be combined with other factors for comprehensive consideration in practical applications to identify targets with investment value. This factor assumes that compared with newly listed companies, companies that have been operating in the public market for a longer time are more likely to establish stable profitability, a solid brand effect and a more complete governance structure, thereby providing relatively more stable investment returns in the long run. However, this does not mean that companies that have been listed for a long time are necessarily better than companies that have been listed for a short time. It needs to be analyzed in combination with specific corporate conditions and market environment.