Taiwan's working-age population in 2070 is projected to shrink to less than half of the current total, a government agency said, as the self-ruled island has been struggling to counter security threats from China.

The number of the working-age population, or people aged 15 to 64, is estimated to drop from this year's 16.3 million to 15.07 million in 2030 and to 7.76 million in 2070, according to a report released last week by the National Development Council.

The agency also said that Taiwan, which has been confronted with a serious aging phenomenon in the aftermath of the low birthrate, will become a super-aged society by 2025, with 20 percent of its population being over 65.

Recently, the Taiwan government has mapped out a number of measures aimed at preventing the birthrate from plunging.

In a bid to tackle the problem of declining population, the Executive Yuan, or cabinet, earlier this month earmarked NT$108.8 billion (US$3.8 billion) in the budget for the new fiscal year starting in January, a 35 percent increase from a year earlier.

As China has been putting military pressure on democratic Taiwan, the island is likely to be forced to boost spending to ease the negative impact of the aging population, which could affect its defense policy against communist Beijing, some pundits said.

Taiwan's total population began to fall after peaking at 23.6 million in 2019. The council expects that it will slide to between 17 million and 15 million by 2070.

Related coverage:

FOCUS: China's large drills near Taiwan raise Japan, U.S. alert level

Another U.S. senator visits Taiwan amid tensions with China

Taiwan plans record military spending amid China security fears