China kicked off its seventh national population census on Sunday with about seven million staff to visit homes for registration work.

Carrying out the census is critical to understand the population size, structure and distribution, said Ning Jizhe, deputy head of the National Development and Reform Commission, at a video conference to promote the national census.

It will provide important and basic information for the national strategy of responding to the challenge of population aging, as well as for the promotion of high-quality development, said Ning.

The census collects data including name, ID number, gender, marital status, education and profession of Chinese citizens.

Ning urged efforts to complete the census with high quality to provide support for major national strategic plans and the scientific formulation of policies.

Since the founding of the People's Republic of China, six national censuses have been completed. Throughout the six decades, China's population has boomed from 600 million (1953) to 700 million (1964), 1.03 billion (1982), 1.16 billion (1990), 1.29 billion (2000), and 1.4 billion (2010).

The nation's demographic structure has changed significantly over time, however, and this year may become an important turning point as annual data over the years shows that population growth has slowed, the pool of the working-age population has been shrinking and the degree of aging has deepened.

This year, the country is preparing a national economic and social development plan for the next five years (2021-2025), so the data is also vital for policymakers.

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