BEIJING, Aug. 25 (Xinhua) -- China added 8,130 km of expressways to its toll road network last year, an increase of 6.5 percent year on year, according to the Ministry of Transport.

The newly-added expressways put the country's total length of fee-collecting expressway at 132,638 km, or 81 percent of the toll roads in China, data from the ministry showed.

In 2017, 15,245 km of first- and second-class toll roads became toll-free, marking a decline of 33.5 percent year on year, according to the ministry.

The country's toll roads registered a deficit of 402.6 billion yuan (about 58.4 billion U.S. dollars) last year, down 2.8 percent year on year.

China is aiming to build and put 5,000 km of expressways into use this year.

The country categorizes its roads into five tiers in terms of traffic volume, with expressway being the top class, followed by first-class, second-class, third-class and fourth-class roads.