Migrant worker Guo Huailiang is planning to live it up a bit in his retirement.

After 19 years living in cramped quarters in Beijing, rising at 5:30 a.m. for a 12-hour shift, the 52-year-old construction worker is socking away money that will allow him to return to his eight-room house and 4-acre (1.6-hectare) plot in the countryside, spend a bit of cash and travel. He is dreaming of trips to Hainan Island, Taiwan and even South Korea.

Multiply Guo by the millions who migrated to China's cities, toiling away in factories and building sites for decades, and you have a hoard of savings that stands to revolutionize China's consumer market. It turns out that Chinese getting old may just help create the balanced economy its leaders have been aiming to engineer.