Before the introduction of the reform and opening, the outputs of freshwater and saltwater fish, relying on natural rivers, lakes and fisheries near the sea, were low. But since 1978, China has stressed artificial aquatic products breeding and at the same time devoted great efforts to developing deep-sea fishing. As a result, the output of aquatic products has risen greatly, increasing by two million tons, on average, every year. Now, more than 20 deep-sea fishing companies have been set up in China, and wholly Chinese-owned and Chinese-foreign joint enterprises have also been established abroad engaging in this business.