SEOUL - South Korea's total population slightly rose for the second straight year thanks to a rapid increase in foreign residents, statistical office data showed Tuesday.

The total population added 0.1 percent, or 31,000, from a year earlier to 51,806,000 on Nov 1 in 2024, after inching up 0.2 percent in the previous year, according to the 2024 census by Statistics Korea.

Foreign residents, who stayed here for at least three months, gained 5.6 percent to 2,043,000 last year, topping the 2 million mark for the first time. It took up 3.9 percent of the country's total population.

More foreigners arrived here for study and jobs amid the extended working visa programs.

Local residents fell 0.2 percent to 49,763,000 in the cited period due to the low birth rate and the aging population, keeping a downward trend for the fourth consecutive year.

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The Asian country has struggled with a chronically low birth rate as young couples delayed or gave up on having babies due to economic difficulties such as high housing prices and stubborn unemployment.

The working-age population aged 15-64 decreased 0.8 percent over the year to 36,263,000 in 2024, accounting for 70.0 percent of the total population.

The proportion of the working-age population has continued to go down since 2018.

The elderly population aged 65 and above swelled 5.3 percent to 10,122,000, but those under the age of 14 declined 3.5 percent to 5,421,000.

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The aging index, or the number of those aged 65 and older per 100 people aged 14 and younger, jumped to 186.7 in 2024 from 122.3 tallied in 2019.

Among 43,065,000 local residents above the age of 18, a total of 12,736,000 people, or 29.6 percent, remained unmarried in 2024. It was up 0.5 percent compared to the previous year.

The total number of households reached 22,997,000 in 2024, up 1.2 percent from a year earlier.

The number of households residing in Seoul and its surrounding metropolitan area stood at 11,458,000 in 2024, or 49.8 percent of the total households.

The average number of family members per household shrank 0.03 over the year to 2.19 last year.

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The number of single-member households expanded 2.8 percent to 8,045,000, making up 36.1 percent of the total households.

The proportion of one-person households kept growing from 15.5 percent in 2000 to 27.2 percent in 2015 and 35.5 percent in 2023.

The continued growth in single-person households came from the aging population and the reluctance among the younger generation to get married.

The total number of houses climbed 1.7 percent from a year earlier to 19,873,000 on Nov 1 in 2024, after increasing 2.0 percent in the previous year.

After peaking at 5.4 percent in 1995, the annual growth rate of houses had roughly been on the decline.

The number of houses in the Seoul metropolitan area ran to 9,285,000 last year, accounting for 46.7 percent of the total.