Analysis of the Impact of Age and Regional Characteristics on Population Change: Focusing on the Resident Population Census from 2009 to 2020

According to the population projections by Statistics Korea, the working-age population is expected to decline by over 3.5 million people from its peak in 2019 to 2030. Additionally, Republic of Korea has the lowest total fertility rate of 0.84 births per woman among OECD countries. The population decline in Korea is a significant challenge accompanied by population aging. However, there are some regions in the metropolitan area where population growth is observed. In this study, we aim to identify the key factors influencing population change using machine learning analysis. The factors consider include population composition by age group and various social factors such as employment, housing, culture, health-care, and welfare at the community level. The analysis results show that changes in population size in the age groups of 50∼54 and 45∼50 had a high degree of influence on the change in the population of the region. These age groups have a high proportion in the population composition of Korea and are associated with active economic activities in the working-age population. On the other hand, age groups with older individuals have less influence on population change. In terms of regional characteristics, the analysis reveals that the supply of housing, particularly apartments, had a strong impact on population change. The availability of apartments indicates not only increases housing supply but also the development of convenient facilities and job creation. Rental prices are found to have a negative influence, while property prices have a positive influence on population change. Although this study aims to examine multiple factors affecting population change, further analysis based on regional characteristics and typologies could yield more improved research outcomes.