China's elementary and secondary school extracurricular tutoring market is booming, with a recent report saying that it has reached nearly 800 billion yuan ($115 billion) in 2016.

137 million elementary and secondary school students in China were enrolled in extracurricular tutoring institutions this year, according to a report on the extracurricular tutoring industry released by the Chinese Society of Education on December 28.

There are said to be 7 million teachers for elementary students nationwide, and 8.5 million for secondary students.

The report shows China's elementary and secondary school extracurricular tutoring operations have mushroomed since the 1990s due to growing recognition and demand by parents.

The country has from 180 million to 200 million elementary and secondary school students at the moment.

Math teachers occupy about 40 percent of the tutors interviewed, while English and Chinese tutors each account for 20 percent, according to the report.

Meanwhile, the report indicates that there are problems that cannot be ignored. A major problem is that many institutions over-emphasize earnings and thus ignore improving teachers' abilities.

Among the parents interviewed, nearly one-third said that they were concerned about the tutors' professional quality, the report says.

In addition, the educational background and level of performance among tutors also varies.

The report shows 83.9 percent of the teachers interviewed hold a bachelor's degree, and 63.1 percent have a degree in education.

40.8 percent of them have three to five years teaching experience and about 29.5 percent have teaching experience of only one or two years.