HONGKONG was the biggest contributor to Australia's A$1.1 billion (HK$5.67 billion) education industry last year. Full fee paying students from Hongkong paid A$210 million for their Australian education in 1992, according to new figures released by the Department of Education, Employment and Training. The acting secretary of the department's international students branch, Bob Goddard, said spending by overseas students had risen from A$50 million in 1986, when there were 2,168 full-paying overseas students, to 52,540 last year. Hongkong was the largest source of students, with 9,721 last year, followed by Malaysia with 8,886 students. There were 5,287 students from China, 4,680 from Singapore, and 2,942 from Japan. Mr Goddard said education had not featured in Australia's export earners ''big league'' until two years ago, but now was almost as important to the economy as wheat, which brought in A$1.5 billion last year.