China is more urban today than ever before. More than thirty-six percent of the Chinese population lives in a city or large town. The urban growth rate is quickly increasing. Shenzhen, China was once a rice-growing village in the late 1970s, and now is a city of over three million residents today. The growth rate of urban residents is expected to reach between fifty and sixty percent within the next twenty years. .
Many of the world's mega cities are located in China, such as Beijing, Shanghai, Hong Kong, and Tianjin. Mega cities are cities with populations over eight million. It's expected that by the year 2015 the population of China will increase by fifty percent. .
Shanghai is China's largest city. There are about 2,118 people per square kilometer living in Shanghai. In 1995 Shanghai had a population of 13.58 million people. It is expected that its population will increase to 17.97 million in the next 20 years. That is an increase of approximately thirty-two percent. China's second largest city, Beijing, had a population of 11.3 million in 1995. It is expected population in twenty years is 15.57 million. Tianjin and Hong Kong are also expected to have a high urban growth rate in the next twenty years. .
Population growth has brought a series of problems to China. This is the reason behind its policy of family planning. China encourages late marriage and late childbirth. According to China's marriage law rule, a man should be twenty-two when he marries and a woman should be twenty. If a woman is older than twenty-four when she has a baby, China considers it a late childbirth. For years, China allowed couples to have only one child. Recently the state has adopted a more tolerant policy toward minority ethnic groups. If China hadn't taken on the family planning program, it would have 260 million more people than the current population. Without this extra population burden, life in China has improved.