Among them, 66.7 percent moved within their cities or provinces, while 33.3 percent chose to cross city limits.

The population mobility rate -- the number of those changing residence for every 100 people -- fell 0.8 percentage point to a 43-year low of 14.4 percent last year.

"A protracted slump in the economy affected the slowdown in population movement last year," said Lee Jie-youn, head of the agency's population trend team. "It is also because of the decreasing number of young people in their 20s and 30s, who easily change their residence for occupational and academic reasons."

The South Korean economy grew 2.7 percent last year, slightly up from 2.6 percent growth in 2015, far below than its earlier expansion of 3.3 percent in 2014 and 6.5 percent in 2010.

She said the government's tightened regulations on mortgage loans in a bid to reduce household debt also heavily affected the downside trend in population mobility.

A net 140,000 people moved out of Seoul last year, while a net 134,000 people moved to Gyeonggi Province, which surrounds the capital. Housing prices in the province are usually lower than those in Seoul. (Yonhap)