BEIJING — China's fixed-asset investment in the transport sector maintained steady growth last year, official data showed.

The total fixed-asset investment increased 7.1 percent year-on-year to nearly 3.48 trillion yuan (about $541.6 billion) in 2020, according to the Ministry of Transport.

The growth rate was the highest in the last three years, said the ministry.

By the end of 2020, the operating mileage of China's railway network reached 146,000 km. The country had a total of 5.2 million km of highways, of which expressways represented 161,000 km.

There were 2,592 berths of 10,000-ton-class or above and 241 certified civil airports throughout the country by the end of last year.