Statistics data from the Seoul Metropolitan Government predicts that in 27 years, the working-age population between 15 and 64 would drop 26 percent to 5.99 million and senior citizens aged 65 and over are expected to grow 172 percent to 2.95 million.
Currently an average of 7.4 working people support each senior citizen.
The demographic change is feared to squeeze the city’s workforce, threatening growth and pension systems.
The data based on a survey by the Statistics Korea also indicated that the number of youth aged 1 to 14 is forecast to decrease by 25 percent to 1.03 million.
As a result, young people would comprise 10.3 percent, the labor force 60.1 percent and senior citizens 29.6 percent of the Seoul population.
South Korea has one of the lowest birth rates in the world, with an average of 1.24 babies per household. Korea is also rapidly becoming an aged society due to increased lifespan, with over 14 percent of the population being 65 and older.
A separate survey in 2011 by the municipal authorities showed that 31.7 percent of citizens are willing to pay more taxes for the welfare of senior citizens, an increase from 26.1 percent in 2007.
The number of senior citizens over 65 prepared for retired life has increased from 35 percent to 47.1 percent. Among elders over 60, 97.3 percent wished to receive welfare services. Among the options, 34.1 percent wanted health examinations, 24 percent wanted nursing and 14.2 percent wanted housework assistance.
The number of working citizens over 60 also hit 471,000 last year, a 50.5 percent increase from 313,000 in 2001.