State-controlled PetroChina Co. Wednesday posted a 6.2% decline in its third-quarter net profit on lower contribution from upstream businesses amid weaker oil demand. China’s largest oil company by production capacity said third-quarter net profit fell to 27.9 billion yuan from 29.8 billion yuan a year earlier. Revenue rose 3.2% to 600.6 billion yuan from a year earlier. The company’s crude oil output rose 0.3% in the first nine months. Write to Yvonne Lee at