The 20 countries facing population collapse

Charly Triballeau / AFP / Getty

Japan is projected to have a population decline of 16.3% between 2020 and 2050.

• Many countries face serious demographic headwinds in the decades to come.
• Low birth and immigration rates could lead to rapidly aging and shrinking populations in these areas.
• Using the UN's population estimates, we found the 20 countries projected to have the largest percent decline in population between 2020 and 2050.
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While the world's population is expected to continue growing for decades to come, many countries face serious demographic headwinds, with low birth and immigration rates leading to aging and shrinking populations.

Japan is facing a "demographic time bomb" as young people in that country forego having children. The BBC recently highlighted attempts to slow Bulgaria's population decline - the fastest in the world - by improving educational and economic opportunities in the country, making it more attractive for younger workers to stay rather than emigrating elsewhere in the European Union or to other countries. And while the United States is projected to keep growing for the foreseeable future, Americans are waiting longer to have children, suggesting a gradually aging population.

To get a sense of the demographic challenges confronting different parts of the world, we found the countries projected to have the most rapidly shrinking populations in the next few decades.

The United Nations regularly publishes demographic projections estimating how the world's population could change over the next several decades. Using the UN's middle-of-the-road estimates for fertility, mortality, and international migration, we found the 20 countries projected to have the largest percent decline in population between 2020 and 2050.

For the purposes of our analysis, we excluded subregions or overseas territories of other countries, like the French territory of Wallis and Futuna, which is projected by the UN to have an 18.7% population loss over the next three decades.

Here are the fastest-shrinking countries in the world: