In the coming weeks, nearly all Chinese families will be involved in a grand national project – the seventh national census. 

Starting from November 1, seven million census workers will spread out across the country, collecting names, gender, ethnicity, marital status, home address, educational and professional information from families. Foreign residents in China will also have their information collected. 

China's national census is conducted about every 10 years. Previous censuses took place in 1953, 1964, 1982, 1990, 2000, and 2010. The last census found that the country's population grew from 1.29 billion to 1.37 billion, with a growth rate only half of the rate between 1991 to 2000. 

The national census provides a panoramic view of China's demographics and how the population is distributed regionally, which is integral for policymaking. As China is suffering from an aging and shrinking population, timely adjustments to the country's population policy will be crucial to sustaining its economic growth. 

China's demographics is now similar to the shape of an hourglass – with large number of the elderly at the top and shrinking number of youths at the bottom. 

According to a report by the Chinese Academy of Social Sciences, due to a decline in birthrate and an increase in life expectancy, a population contraction may begin in 2027. The declining population could hurt China's future economic prospect. The labor force is shrinking and factories nationwide report difficulties in recruiting young workers. 

In 2010, the census found that the number of people aged 14 or younger was down 6.2 percent from the figure collected at the previous census, while the number of people aged above 60 years old was about 177.6 million, accounting for 13.3 percent of the total population, 2.93 percent higher than in 2000. 

China started easing its one-child policy in late 2013, aiming at a boost in births. In 2015, China replaced the one-child policy with a new one that allows couples to have two children. 

In 2016, the number of births rose by 1.3 million from the previous year to 17.86 million, according to data from the National Bureau of Statistics. But the easing of the policy failed to produce a baby boom that some expected to see. Since 2017, the birth rate fell for three consecutive years. 

Life expectancy, on the other hand, has been increasing rapidly in China. The last census found that the life expectancy increased from an average of 67.77 in 1982 to 74.83 in 2010. 

As a result, the elderly share of the population has expanded. By the end of 2019, over 176 million people were aged over 65 in China, accounting for 12.6 percent of the population. 

According to the China Statistical Yearbook 2019, at least six provinces and municipalities have reported more than 14 percent of their population over the age of 65, signifying that they have become moderately aging societies. 

The continuous decline of working-age people underscores the challenge of supporting the growing number of seniors. China's dependency ratio for retirees now stands at around 17.8 percent, meaning that each senior resident needs to be supported by six people. 

Soaring pension expenses and increased medical costs will pose challenges to the country's fiscal capacity. Reforms have been carried out to address shortfall in the pension system.  

Alongside rapid aging is the fast urbanization of the population. China is home to the largest flow of internal migration in world history. The 2010 national census found that China's urbanization rate increased from 20.9 percent in 1982 to 49.7 percent in 2010. 

The massive outflow of young labor force has resulted in the "hallowing-out" of rural areas. Many villages are now populated by elderly residents with no adult children to take care of them. Industrialization and urbanization are blamed by some of weakening the traditional support structure in rural China, leading to a weakened role of the extended family and community. 

Changes in China's demographics are likely to upend the country's socioeconomic priorities and their ramifications can be long-lasting. Adjustments to the country's retirement, pensions and education systems are needed to avoid a demographic crisis to loom.