Shanghai_reutersFor years, China was a promised land for expanding multinationals and manufacturers, drawing hordes of expatriate employees eager to capitalize on the country’s billion-plus consumers. Could those days be over?

A new study by UniGroup Relocation, which moves over 260,000 families per year worldwide for work, suggests they might be.

According to the company’s customer data, twice as many people moved out of China than into the country in 2014.

The outflow could be pegged to expiring work contracts, which typically tie expats to China for two to three years, according to UniGroup. But there are other reasons as well: rising costs of living, a desire to reengage with the home office and the apocalyptic pollution, which even Beijing’s mayor has said makes the city “unlivable.”

The trend is also driven by a shift in global economic winds, the company says. China’s slowest growth since 2009 –which leaders have…