BEIJING, Jan. 1 -- China's Beijing-Tianjin-Hebei region continued to witness development progress in 2022, with innovative and green development serving as the main drivers, official data showed.

The Beijing-Tianjin-Hebei regional development index hit 145 points in 2022, up 5.1 points from the previous year, according to the National Bureau of Statistics (NBS).

Sub-readings of innovation and green development were the main drivers of the overall index growth, up 11.6 and 7.7 points, respectively, when compared with 2021.

The region posted 4.25 percent in terms of the ratio of research and development spending to gross domestic product, which is 0.18 percentage points higher than the figure for 2021.

Total goods exports and imports of this region increased 10.2 percent year on year to 757.58 billion U.S. dollars in 2022.

The region also enjoyed better air quality in 2022. The average density of PM2.5 -- fine particulate matter that causes smog -- dropped to 37 micrograms per cubic meter.

China in 2015 rolled out a plan for the coordinated development of Beijing, Tianjin and Hebei. Progress has been made in many fields including environmental protection, public services and transport.