Japan is an island country stretching along the northeastern coast of the Asian continent. It consists of 4 main islands--Hokkaido, Honshu, Shikoku, and Kyushu, from north to south--and more than 6,800 smaller islands. With a total land area of 377,719 square kilometers, Japan accounts for less than 0.3 percent of the total land area of the world. Of its entire land area, 73 percent is mountainous and the remaining 27 percent is relatively flat. Thus the arable and habitable land is extremely limited.
The population of Japan as of October 1989 was 123 million, ranking seventh in the world with about 2.4 percent of the world population. The average annual rate of population increase from 1986 to 1989 was a little more than 1 percent. In 1989 the rate was as low as 0.38 percent. The population growth of Japan is caused mainly by natural increase, for net international migration is negligible. The birth rate declined sharply from its high level during the postwar baby-boom period of 1947-49 and became 10.1 per 1,000 population in 1989. In the same year the death rate was 6.5 per 1,000 population, the same as in the previous year. As a result, the rate of natural increase recorded was 3.7 per 1,000 population. The infant mortality rate improved to 4.7 per 1,000 live births in 1989. Except for the death rate, these ratios have been declining every year for several years.
The life expectancy at birth of the Japanese has shown a remarkable improvement and has been among the highest in the world. It declined slightly in 1988, when it was 75.54 years for males and 81.30 years for females.
The age structure of the Japanese changed markedly from the typical pyramid form with a broad base in the 1930s as a result of the decrease of the birth rate