If you want to understand what happens when people stop having kids while life expectancy keeps rising, look no further than Japan.
The country’s population is falling faster than ever before, and it’s prompted economists to call the nation a “demographic time bomb” — defined as a place where fertility rates are falling at the same time that longevity is increasing.
Some experts have even created their own doomsday clock for when Japan will go extinct.
But Japan just happens to be the most extreme case of what’s happening in a number of countries around the world. People are working longer hours, fertility rates are falling, and future economies are being put at risk.
Here are just some of the countries that could become demographic time bombs over the next 20 years.
In Hong Kong, the government is faced with a striking gender imbalance; women outnumber men at nearly every age bracket above 25.
The imbalance is mainly due to men seeking women up north, in mainland China, as the women there are sometimes viewed as less choosy than in Hong Kong, according to experts in gender studies. Each year, the city also brings in thousands of foreign domestic helpers (who are almost always female) from countries like Indonesia and the Philippines.
The two trends have coalesced into a tense climate for younger generations.
A fifth of the world's population lives in China. But with a fertility rate of 1.60 and a culture that is becoming more reclusive, men and women are increasingly choosing not to date, let alone get married and have kids.
There are entire industries devoted to livestream stars, with millions of viewers -- men, primarily -- who pay to watch people sing, dance, or just eat soup. Multiplied out, they have created a generation that often prefers alone time.
Many of the challenges facing Japan are making their way to South Korea -- namely, long work hours with less consideration for family planning. But that hasn't stopped the government from trying other schemes.
In 2016, the US had a record-low birth rate, according to provisional 2016 data from the Centers for Disease Control. That brought the general fertility rate among women 15 to 44 to 62.0 births per 1,000 women.
Shifting views on gender roles over the years have caused more women to enter the labor force. In addition, millennials are increasingly choosing to forego parenting in an effort to move up in their careers, pay off their massive student debt, and gain financial independence from their parents.
Fertility rates in Spain are creeping downward while unemployment is rising: About half of all young people don't have a job. It's the second-highest rate in Europe, behind Greece.
To combat the worrying trends, the Spanish government hired a special commissioner, Edelmira Barreira, in January 2017 to investigate and find ways to reverse the trend.
With a fertility rate of 1.43 -- well below the European average of 1.58 -- Italy has taken a controversial approach to encourage citizens to have more kids.
'Beauty knows no age, fertility does,' one ad said. 'Get going! Don't wait for the stork,' said another.
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