Well, there are many factors, but one important factor is, the rise of the Internet has competed with -people used to buy The Wall Street Journal to get data like this.

其实有很多因素,但是最主要一点是,来自网络的竞争,人们过去买《华尔街日报》来获取这些数据

耶鲁公开课 - 金融市场课程节选