Southwest China's Chongqing Municipality reported a slower economic growth last year as its traditional pillar industries lost steam.

Its GDP expanded 6 percent year on year to 2.04 trillion yuan ($299 billion) in 2018, the municipal statistics bureau announced Tuesday.

Chongqing's economy expanded 9.3 percent year on year in 2017, ending a 15-year streak of double-digit growth.

Data showed the industrial output for the auto industry in Chongqing declined 17.3 percent year-on-year in 2018 amid a sluggish car market.

The city has turned to new industries such as big data, artificial intelligence and smart hardware for new growth momentum.

The industrial output of the high tech industry in Chongqing increased by 13.7 percent year-on-year in 2018, the bureau said.

Yi Xiaoguang, director of the Chongqing Institute of Comprehensive Economic Research, said Chongqing was seeking quality growth as its high tech industry and new business patterns reported fast growth.