Aerial photo taken on March 23, 2018 shows a self-driving tractor sowing cotton seeds in the field at Yaha Township of Kuqa County, northwest China's Xinjiang Uygur Autonomous Region. China's GDP reached 19.88 trillion yuan (about 3.2 trillion U.S. dollars) in the first three months of 2018, up 6.8 percent year on year at comparable prices, according to the National Bureau of Statistics (NBS). (Xinhua/Hu Huhu)