The number of Japanese students at U.S. colleges and universities has dwindled while Chinese students have increased for the eighth consecutive year, according to a yearly report by the Institute of International Education (IIE).

In 2012 the number of Chinese students at U.S. colleges and universities increased by 21.4 percent to 235,598, 12 times the number of Japanese students, which fell by 2 percent to 19,568.

While the number of Japanese students decreased overall, those not pursuing degrees, including those gaining college credits in short-term English learning programs, increased by 5.6 percent.

The country that sent the most students to the United States from 1994 to 1999, Japan has dropped to seventh due to factors including its rapidly aging population, the corporate recruiting cycle, and increases in students from India, China, South Korea and Saudi Arabia, the report said.

Chinese students made up nearly 30 percent of all international students studying in the United States in the 2012-2013 school year, more than the next three largest groups — India, South Korea and Saudi Arabia — combined.

The percentage of Chinese students is "the largest concentration of students from any one place of origin that the U.S. has ever seen," according to Rajika Bhandari, IIE's deputy vice president for research and evaluation.

The number of Chinese students in the United States has grown in double-digit leaps since 2007. The majority of Chinese students in the United States are at the graduate level, though undergraduates alone increased by 25 percent in 2012.

The report also found that the number of Americans studying in Japan, which had fallen by a third from around 6,100 to around 4,100 in the 2010-2011 school year because of the earthquake and tsunami, bounced back to 5,283 in the 2011-2012 school year.