The S&P 500 is 500 companies, who are major companies, so these tend to be mature companies and they tend to be in the dividend-paying stage.

标准普尔500指数包括500家大公司,这些一般都是成熟期的公司,他们一般都处于需要支付股利的阶段

耶鲁公开课 - 金融市场课程节选

Those are the two biggest rating agencies in the U.S. today and they're extremely powerful organizations because they --Standard & Poor's also does letter grades, a slightly different system, but almost the same.

如今他们是美国最大的两家评级机构,而且他们是非常权威的组织,标准普尔也进行字母评级,体系上有些区别,但基本相同

耶鲁公开课 - 金融市场课程节选