自从Modigliani and Miller(1958)发表其资本结构领域具有开创性著作(MM理论)以来,企业融资行为的理论研究与实证分析不断创新。西方发达国家公司的融资特点与啄食顺序理论模式基本上相一致,是以内源融资为首要,债务融资次之,股权融资的比重最小(Mayor,1990;Rajan and Zingales,1995)。近年来,作为世界上经济最发达的美国,其企业不但减发新股,而且还从股票市场回购了6000多亿美元 Since Modigliani and Miller (1958) has published seminal works (MM Theory) in the field of capital structure, the theoretical research and empirical analysis of corporate financing behavior have been continuously innovated. The financing characteristics of the western developed countries are basically consistent with the theoretical model of the pecking order. The first is internal financing, the second is debt financing, and the second is equity financing (Mayor, 1990; Rajan and Zingales, 1995). In recent years, as the most economically developed U.S. in the world, its enterprises have not only reduced their new shares, but also repurchased more than 600 billion U.S. dollars from the stock market