Gyeonggi, a province neighboring Seoul, gained 134,000 residents. Sejong, which hosts many of the economy-related ministries and government agencies, added 30,000 people to its population.

The exodus out of Seoul sped up throughout last year, statistics indicated. In the first quarter, 23,885 people left the capital. The number increased to 34,680 in the second quarter, 38,426 in the third quarter and to 43,266 in the fourth quarter.

"Such increase shows a trend in which people burdened by expensive housing costs relocate to other cities with relatively better economies to look for better jobs," an official at Statistics Korea said.

Real estate industry records put average home rental fees in Seoul at slightly over 400 million won ($350,416) in 2015, more than double the 165.86 million won back in 2005. (Yonhap)