China’s birthrate dropped to a new low in 2020, underscoring the demographic challenge facing the government as it tries to deal with a shrinking labor force and growing population of elderly people.

There were 8.5 births per 1,000 people in the country last year, the lowest in data extending back to 1978, according to the latest yearbook from the National Bureau of Statistics.

The government didn’t give reasons for the tumbling birthrate, but the new figures confirm population growth in the world’s No. 2 economy is slowing dramatically, with some demographers estimating it could start falling as soon as this year. The number of newborns may decline again this year from the 12 million born in 2020, a health commission official said in July.