The population of registered residents in South Korea has decreased for the fourth straight year as the birth rate continues to decline.

According to the interior ministry on Wednesday, as of December 31 of last year, the number of registered residents fell by 113-thousand-709 compared to the previous year with a total of 51-point-33 million.

The natural population decline, meanwhile, came in at 118-thousand-881 as the 235-thousand-39 births in 2023 were outpaced by deaths at 353-thousand-920.

By age group, those in their 50s accounted for the highest proportion of the population at 16-point-94 percent, followed by those in the 40s at 15-point-44 percent, 60s at 14-point-87 percent, 30s at 12-point-81 percent, 70s and older at 12-point-31 percent.

Those in their 20s accounted for 12-point-07 percent, with a sharp drop-off for teenagers at nine-point-06 percent and children under ten years of age at six-point-49 percent.

Last year was the first time in the nation's documented history that those in their 70s and older exceeded those in their 20s.