Once the world's most populous country, China was overtaken by India in 2023, with Beijing seeking to boost falling birth rates through subsidies and pro-fertility propaganda.

The population stood at 1.408 billion by the end of the year, Beijing's National Bureau of Statistics said, down from 1.410 billion in 2023.

The decline was less sharp than the previous year, when it was more than double the fall reported for 2022, data showed.

China ended its strict "one-child policy", imposed in the 1980s over overpopulation fears, in 2016 and started letting couples have three children in 2021.

But that has failed to reverse the demographic decline for a country that has long relied on its vast workforce as a driver of economic growth.

Many say falling birth rates are due to the soaring cost of living, as well as the growing number of women going into the workforce and seeking higher education.

Population decline is likely to continue due to gloomy economic prospects for young people and as Chinese women "confront entrenched labour market gender discriminations", Yun Zhou, a sociologist at the University of Michigan, told AFP.

People over 60 are expected to make up nearly a third of China's population by 2035, according to the Economist Intelligence Unit, a research group.

- 'Trend won't change' -

Data released on Friday showed that the population aged 60 and over reached 310.31 million -- just a few percentage points short of a quarter of the country and an increase from nearly 297 million recorded in 2023.

However, the data also showed China's birth rate -- among the lowest in the world -- ticked up slightly from the previous year to 6.77 per 1,000 people.

"This uptick is unlikely to last, as the population of childbearing-age women is projected to decline sharply in the coming decades," said Zhao Litao, a senior research fellow at the National University of Singapore's East Asian Institute.

"In the long term, the trends of declining births, overall population contraction, and rapid ageing remain unchanged."

He Yafu, an independent demographer in China, put the uptick in births down to women who deferred having children during the Covid-19 pandemic giving birth. There was also an increase in marriages in 2023 and 2024, the auspicious Year of the Dragon.

However, "the general trend of total population decline won't change", He told AFP.

"Unless strong policies to encourage childbirth are introduced... the proportion of the elderly population will continue to rise."

Officials said in September they would gradually raise the statutory retirement age, which was set at 60 and among the lowest in the world. It had not been raised for decades.

The rules took effect from January 1.

China's previous retirement age was set at a time of widespread scarcity and impoverishment, before market reforms brought comparative wealth and rapid improvements in nutrition, health and living conditions.

The world's second-largest economy now has to contend with slowing growth, while a fast-greying population and a baby bust have piled pressure on pension and public health systems.