进入80年代以来,美国三大电视网(ABC、CBS、NBC)的市场占有率持续下降;而在此之外的独立电视台在电视市场上受欢迎的程度则相应提高了。由于美国放宽了对新设电视台的限制,致使新台如雨后春笋、层出不穷,而新台大多希望进入独立电视市场,成为独立电视台,结果是,1980年全美只有112个独立电视台,1987年发展到371个。7年间增加了两倍多。最近几年,电缆电视用户也有显著增长。美国电缆电视事业开始于第二次世界 Since the 1980s, the market share of ABC, CBS and NBC in the United States has been on the decline. However, the independent TV stations outside of this network have been more and more popular in the television market. As the United States relaxed restrictions on new television stations, new stations mushroomed and emerge incessantly. However, most of the new stations wanted to enter the independent television market and become independent television stations. As a result, there were only 112 independent television stations in the United States in 1980, up from 371 in 1987. Over seven years more than tripled. Cable television subscribers have also seen significant growth in recent years. American cable television business began in the second world