Being looked after by his son and three daughters who live in the same community in Shanghai, Xia Hongqi, 91, is living his twilight years in the traditional Chinese way.

Xia is in good health and satisfied with the situation. He says he is lucky, because the way families in China support their elders had transformed dramatically in recent years due to the country's changing population structure.

Official statistics show the number of people aged over 60 has exceeded 174 million, accounting for nearly 13 percent of the entire population. The percentage is expected to reach 16.7 percent in the next five years, and about 30 percent by 2050.

One of the ageing problems typically found in China's vast rural regions is the empty-nesters, a term referring to those elderly living alone without the company or immediate care of their relatives.

The number of empty-nesters grows with the rapid increase of young and middle-aged migrant workers leaving their hometowns to seek employment in cities.

According to Wu Yushao, a senior official with the China National Committee on Ageing, more than 40 million or 37 percent of the country's rural elderly are empty nesters.

In central China's Shaoshan, hometown of Mao Zedong, many young people have left to pursue a living in the coastal cities, leaving most of the old behind, said Guo Xin, director of the city's civil affairs authority.

Chen Shiyu and his wife, both in their 60s, have lived in Shaoshan all their lives. The couple's six children have all left for the cities and family reunions were rare.

Chen said they often feel lonely and they had to wait until Lunar New Year to see the children come home and have the grand "annual" reunion dinner.

Although the couple missed their children, they made a decision years ago not to live with them in the city. They don't want to leave their own home and are afraid of city living.

To cope with the ageing problems, the Chinese government has introduced measures to take the country away from the family supporting its elders to government and social support systems doing the work while expanding the pension program.

An option for the empty-nesters is to join the government-supported nursing homes.

One pilot project was introduced in a small and remote village called Kecai, about 2,000 kilometers north of Lhasa, capital of the Tibet Autonomous Region.

The number of seniors living in such centers, however, is growing slowly, as most of the Tibetans are reluctant to give up their traditional way of living.

Gong Bao, 85, and his wife A Zhong, 86, lived in the countryside before they moved into the center. They found that moving-in was a good choice and are satisfied with the condition and atmosphere of the nursing home.

In big cities, the ageing problem is no less serious but even more complicated.

The proportion of seniors over 60 in Shanghai makes up 20 percent of the city's population.

Some elderly say the friendly atmosphere and various activities in the community nursing homes have greatly enriched their lives.

Many rest homes constantly report that they are struggling to cope with overwhelming demand.

The Shanghai government has promised in its 2011-2015 development plan to build a larger and better nursing system for the aged and some political advisors had called for more weight in social support besides the government's efforts in delivering such services.

Some seniors who stay at home are connected to a virtual nursing system through which they could ask for services such as emergency aid, health care, teaching, chatting and psychological care.

Although various methods are being devised to resolve the mounting challenge of China's ageing society, it remains a major challenge to the country.

Dr. Richard Jackson, director of Global Aging Initiative under the Washington-based Center for Strategic and International Studies, says the problem is increasing the burden on the young, because the number of workers available to support retirees and the number of children to support their parents was declining.

China has overtaken Japan as the world's second largest economy, but an older population may slow China's growth, Jackson said.

He cautioned China about relying heavily on the universal pay-as-you-go pension system which many developed countries have adopted but which is no longer deemed sustainable.

He also suggested China keep the elderly productively engaged and integrated into the broader community and extend the retirement age.