[4] However, in recent years the total fertility rate (TFR) of South Korea has plummeted, leading some researchers to suggest that if current trends continue, the country's population will shrink to approximately 28 million people by the end of the 21st century.

[9][10] Analysts have attributed South Korea's population decline resulting from low birth rates to the country's high economic inequality; including the high cost of living, low wages for an OECD member country, lack of job opportunities, as well as rising housing costs.

[12] In South Korea, a variety of different Asian people had migrated to the Korean Peninsula in past centuries, however few have remained permanently.

In the past, the large proportion of children relative to the total population put great strains on the country's economy, particularly because substantial resources were invested in education facilities.

[18] The decline in the population growth rate and in the proportion of people under fifteen years of age after 1966 reflected the success of official and unofficial birth control programs.

In the late 1980s, their activities included distribution of free birth control devices and information, classes for women on family planning methods, and the granting of special subsidies and privileges (such as low-interest housing loans) to parents who agreed to undergo sterilization.

[18] Decline in population growth continued, and between 2005 and 2010 total fertility rate for South Korean women was 1.21, one of the world's lowest according to the United Nations.

[20] Fertility rate well below the replacement level of 2.1 births per female has triggered a national alarm, with some predicting an aging society unable to grow or support its elderly.

Recent Korean governments have prioritized the issue on its agenda, promising to enact social reforms that will encourage women to have children.

The Korean government (and their failing actions against the birth rate issue) and the worsening economic environment for young people are blamed as the main cause.

[18] Rural areas in South Korea consist of agglomerated villages in river valleys and range from a few houses to several hundred.

[citation needed] Low birth rates have discouraged South Korean doctors from entering pediatrics out of the fear that the field has no future.

Due to how medical insurance is structured in South Korea, pediatric care relies especially on volume to compensate for its low reimbursement rates.

If employers were to choose to maintain operations in South Korea, there is a possibility that they might incur higher costs in retraining or upgrading the skills of this group of middle-age workers.

Due to the very low birth rate, South Korea is predicted to enter a Russian Cross pattern once the large generation born in the 1960s starts to die off, with potentially decades of population decline.

[21] Like other newly industrializing economies, South Korea experienced rapid growth of urban areas caused by the migration of large numbers of people from the countryside.

There was a striking contrast with Japan, where Edo (Tokyo) had as many as 1 million inhabitants and the urban population comprised as much as 10% to 15% of the total during the Tokugawa Period (1600–1868).

During the post-Korean War period, rural people left their ancestral villages in search of greater economic and educational opportunities in the cities.

By the late 1960s, migration had become a serious problem, not only because cities were terribly overcrowded, but also because the rural areas were losing the most youthful and productive members of their labor force.

[18] In 1970, the Park Chung Hee government launched the Saemaul Undong (New Community Movement) as a rural reconstruction and self-help movement to improve economic conditions in the villages, close the wide gap in income between rural and urban areas, and stem urban migration—as well as to build a political base.

Despite a huge amount of government sponsored publicity, especially during the Park era, it was not clear by the late 1980s that the Saemaul undong had achieved its objectives.

Growth was particularly spectacular in the southeastern coastal region, which encompasses the port cities of Busan, Masan, Yosu, Jinhae, Ulsan, and Pohang.

The concentration of factories in urban areas, the rapid growth of motorized traffic, and the widespread use of coal for heating during the severe winter months caused dangerous levels of air and water pollution,[18] issues that still persist today even after years of environmentally friendly policies.

Since The People's Republic of China and South Korea established their diplomatic relationship in 1992, the number of Chinese immigrants, majorly Joseonjok, has continued to increase.

[41][failed verification] The relationship between Vietnamese and Koreans date back to when Lý Dương Côn left for Goryeo after succession of power dispute.

For example, the Gyeongsang dialect spoken around Busan and Daegu to the south is often perceived to sound quite rough and aggressive compared to standard Korean.

The largest group, about 1.7 million people, lived in China, the descendants of the Korean farmers who had left the country during the Japanese occupation.

Smaller Korean communities formed in Australia (100,000), Central and South America (45,000), the Middle East (12,000), Western Europe (40,000), New Zealand (30,000), other Asian countries (27,000), and Africa (25,000).

[18] Because of South Korea's rapid economic expansion, an increasing number of its citizens reside abroad on a temporary basis as business executives, technical personnel, foreign students, and construction workers.

Also, sizeable number of migrants from countries with primarily multicultural immigrant population, such as Australia, Canada, United States, and Japan are also of Korean ethnic descent.