Nov. 22 - The number of Chinese mainland students going to study in the United States hit a record high this year, up 40 percent from last year and double the figure in 2004, the US embassy said Wednesday.About 51,500 student and exchange visitor visas have been issued to mainland Chinese so far this year, Michael Regan, US consul general in China, told a press conference, adding that the approval rate is about 80 percent.Diane Sovereign, assistant press officer of the US embassy, said the increase reflects Chinese students' growing interest to study in the United States as well as the rising visa approval rate.Ministry of Education spokesman Wang Xuming said he welcomed the trend "that is conducive to the promotion of international student exchanges".After India, the Chinese mainland is the second largest source of overseas students for US universities. Frank Mok, an official with the American Center for Educational Exchange, said he is optimistic that more student visas will be issued next year.