BEIJING, Jan. 24 (Xinhua) -- Academic test-takers for the International English Language Testing System (IELTS) on the Chinese mainland are shown to have improved in all four language skills of listening, speaking, reading and writing from 2012 to 2018, the China Daily reported Thursday.

A new IELTS white paper said the average score for the test-takers on the mainland reached 5.72 points for the 2017-18 period, 0.16 points higher than the 2012-13 period.

Reading scores improved the most, from 5.9 points in the 2012-13 period to 6.15 points in the 2017-18 period, while speaking scores only increased by 0.02 points, said the white paper released Wednesday by the British Council, co-owner of the IELTS.

Candidates in Shanghai ranked first place in the four skills, said the white paper, based on the results of all mainland IELTS test-takers from June 1, 2017 to May 31, 2018.

Undergraduate students continue to be the main group of IELTS test-takers on the mainland, accounting for 52 percent, while those under age 18 form the second-largest group, at 18 percent of the total, the white paper said, adding that 88.6 percent of the test-takers had overseas studies in mind.

Chu Zhaohui, a senior researcher at the National Institute of Education Sciences, said the English proficiency of people in China has improved steadily thanks to education reforms adopted by the government and the opening-up of Chinese society.

While he also noted the greatly varying English proficiency across the country and the challenge to "lift everybody to the same kinds of opportunities for language learning."