Population growth is continuing to slow in the U.S. and China — the world’s top two economies — but that’s not necessarily a bad thing.

Why it matters: While population trends can be difficult to change, there is unlikely to be a “point of no return" where they can't be reversed — if government leaders proactively address the foundational causes, like the burdens and costs of child care or fears of immigration.

• Population growth impacts economic growth because it can increase innovation, workers, and goods produced and consumed.

By the numbers: The United Nations projects that the world population will grow to 9.7 billion people in 30 years, from about 7.7 billion as of 2019. 

• More than half of that growth will be concentrated in nine countries, including the U.S.
• Over the same time period, China will be one of 55 countries or areas where population is expected to decline by at least 1%.
• Globally, the number of young people entering their reproductive years now is larger than their parents’ generation — so even if the global level of fertility were to fall immediately to around two children per woman, births would still exceed deaths for several decades, according to the U.N.

Yes, but: “We focus way too much on the percent growth like quarterly GDP,” American Enterprise Institute adjunct fellow Lyman Stone tells Axios. “We should think about what people want. What level of immigration people want. What age would people like to die.” 

• The U.S. is currently failing to achieve the average social preference across all three demographic trackers — immigration, life expectancy, and fertility are all trending down.
• “When pretty normal desires are not being fulfilled, that’s an indicator that society has a problem," Stone says.

Americans still want multiple children, but they’re worried about child care costs, their own student debt, a lack of family leave policies, and a pause in their careers.

• These concerns are also limiting family growth in China — on top of a severe gender imbalance caused by the country’s one-child policy and male child favoritism. 

While Beijing has relaxedrestrictions on the number of children families can now have in China, the new policy seeks more to bolster its workforce than to promote population. That’s because at the same time, the Chinese Communist Party is also raising the country’s retirement age, eliminating a key source of child care for Chinese families. 

• In the U.S., President Biden’s plan to start sending monthly payments to families with children is seen as a way to recognize the young as a societal good, not private responsibility.

The big picture: Population is a measure of how many options people have for business partners, customers and romantic relationships — the numbers for which are all likely to improve with a larger society, says Stone.

• What also matters more than absolute population growth is the age distribution of population, especially for economic growth.
• “If you have a lot of young people and relatively fewer older adults, you basically get the distribution China had in 1990, which will guarantee a [large] labor force for economic growth,” says Emma Zang, assistant professor of sociology at Yale University.
• There’s no consensus on how many people the planet can support, since there’s no guarantee that populations will grow as projected or that people will consume food and energy in the same wasteful ways as they have.

The bottom line: If countries want population growth to pick up, leaders must first fix the underlying causes for a slowdown.