A flurry of departures across the US and Canadian units of Chinese state energy firm PetroChina have sparked speculation that the oil trader is reducing its presence in North America, even though the company says it is committed to the region. More than 30 people in its Houston and Calgary offices have left PetroChina since 2016, including heads of desks in crude, financial, natural gas and chemical trading, the company confirmed to Reuters. Sources say that PetroChina had approximately 150 to 200 people at its peak two to three years ago, and now has between 100 and 150. Nearly a dozen sources in New York, Calgary, Houston and Singapore, including current and former employees, told Reuters the departures suggest a shift in mindset among firm management, and there are concerns about a broad pullback from its presence in North America. The sources said North American offices may have expanded too quickly.