The latest population projection for Japan showed that during the next 50 years, the dependency ratio will drastically increase from 0.58 (2010) to 0.94 (2060) and that the population will decrease from 128 million (2010) to 87 million (2060). There is concern that burdens placed upon the working-age population will increase and that the social security system of the nation might eventually collapse. We report here the results of population projections under four scenarios of changes in vital statistics rates that reflect the current demographic policies in Japan. These four scenarios assume that specific vital statistics rates change as follows. Scenario 1 : The total fertility rate will increase to 2.1 (replacement level) in 2010. Scenario 2 : The in-migration rate at 18 years of age will increase to 0.1. Scenario 3 : The start of old age is redefined as 70 years. Scenario 4 : Age-specific mortality at age 65 years or older will double. Scenarios 1 and 2 mitigate the population decrease, but Scenario 1 increases the dependency ratio for the initial 40 years. Scenario 3 drastically decreases the dependency ratio without affecting the population size or structure. Scenario 4 suppresses the increase in the dependency ratio, but decreases the population size. If all four scenarios occurred simultaneously, the dependency ratio in 2060 would remain at the level observed in 2005.
After the Great East Japan Earthquake in 2011, about 40,000 people out-migrated from the disaster-stricken areas of Iwate, Miyagi, and Fukushima prefectures. More females than males out-migrated, probably because females tended to fear the potential health hazards of radioactive leakage. In this study, we evaluated the impact of these migrations following the disaster on the sex ratio of the working-age population of all prefectures in Japan. We used the vital statistics in 2012 and 2010 as parameters that were and were not affected by the disaster, respectively. We estimated the future demographic structure using the demographic indices in 2010 and 2012. This analysis revealed that this disaster-induced migration will decrease and increase the sex ratio in the eastern and western parts of Japan, respectively, in 2032. In the disaster-stricken areas, the percentage of males increased in Miyagi and the percentage of females decreased in Fukushima, resulting in an increased sex ratio in both prefectures. Sex-specific migration after the disaster could result in geographical disparity of the sex ratio in Japan.
The spread of influenza depends on contact among people. Contact rates are known to vary depending on the combination of age groups, which means that the age structure of a population affects the spread of influenza. We herein report how future changes in the population structure of Miyazaki Prefecture, a rural region in Japan, will affect the potential spread of influenza. We also report the results of an investigation on how future fertility changes will modify the potential spread through changes in the population structure. The basic reproduction number (R0) was used as an indicator of spread. The future population structure was projected by the cohort component method. Age-group-specific contact rates were obtained by a questionnaire survey. We found that the R0 of a new type of influenza will not change over the next 100 years if vital statistics remain constant (Scenario 0). If the total fertility rate increases by 10% or 25% from 1.7 (the level in 2011), the R0 in 2111 will be higher than that in Scenario 0. These results suggest that fertility recovery, an urgent demographic policy target in Japan, has the potential to increase the spread of influenza.
The population of Japan began to decrease in 2005, and this trend is predicted to continue in the future. The nation-level population decrease can be mostly explained by a decreased fertility rate, while out-migration played an important role in the population decreases seen in prefectures in nonmetropolitan regions. This study investigated the fertility and in-migration rates required to maintain the population size in the Tohoku region. Six prefectures (Aomori, Iwate, Miyagi, Akita, Yamagata, and Fukushima) and Sendai City were targeted. Using the cohort component method, population sizes after 50 years were projected by assuming various levels of fertility and in-migration rates. A>250% increase in the current fertility rate is needed to avoid population decreases in all prefectures with the exception of Miyagi ; the required level was the highest in Akita (378%). On the other hand, if the in-migration rate could be increased to 200% of the current level, the population of Tohoku would remain at the current size. The fertility and in-migration rates needed to maintain the population of the Tohoku region are unrealistically high ; thus, future strategies based on the population decrease are needed.
The fertility goals stated in the National Population Strategy and the successive Action Plans since 2000 in Jordan have not been achieved. The population growth rate and total fertility rate (TFR) remained at 2.2% and 3.5, respectively. The most recent fertility goal is that the TFR will decrease to 2.5 by 2017 and to a replacement level of 2.1 by 2030 (National Reproductive Health and Family Planning StrategyIII, 2013-2017). This study aimed to project the population and age dependency ratios for 2012 to 2062 under two scenarios (Scenario 1 : TFR declines according to the above fertility goal ; Scenario 2 : TFR moderately declines to 3.0 by 2022 and to 2.1 by 2040). The results showed that the total population will increase from 6.39 million (2012) to 7.93 million (2030) under Scenario 1 and that the age dependency ratio will decrease from 0.68 (2012) to 0.40 (2040) under both scenarios. Although a “demographic bonus” is expected in accordance with a decrease in fertility, the absorptive capacity of labor markets must increase and the availability of equitable and high-quality information and services related to reproductive health and family planning must be enforced.
Indonesia has been the fourth most populous country worldwide during the last three decades. Since the Indonesian government began to proactively promote a family planning program in the 1960s, the total fertility rate (TFR) of Indonesia decreased from 5.61 in 1971 to 2.27 in 2000. Unexpectedly, the TFR increased to 2.41 in 2010 despite the fact that the Indonesian government intended to reduce the TFR to a replacement level by 2010. In this study, by establishing four scenarios of future fertility changes in Indonesia, we projected the population size and structure of the country through 2100. In Scenario S0, the TFR was assumed to remain constant at the current level. In Scenarios S1, S2, and S3, the TFR was assumed to constantly decrease to the replacement level (2.1), to 75% of the current level, and to 50% of current level, respectively, by 2025. In Scenarios S1, S2, and S3, the Indonesian population will begin to decline by the year 2100, while it will continuously increase until the year 2100 in Scenario S0. Indonesia will become an “aging society” by 2025 in all four scenarios and will become an “aged society” in the years 2055, 2047, and 2042 in Scenarios S1, S2, and S3, respectively. The rate of aging in Indonesia will be slower than that in other Asian countries. A “population bonus”, defined as when the working-age population accounts for more than 65% of the total population, will last until around 2070 in Scenarios S1, S2, and S3.
When the demographic transition started in the 1970s in Thailand, internal migration of this country also manifested a turning point. Newly reclaimable vacant land almost vanished in the 1980s, although surplus populations in rural areas were being absorbed by other rural areas with lower population densities until the 1970s. This study analyzed population and internal migration changes in Thailand from 1980 to 2030. Analysis of populations by age group in urban areas (central region and Bangkok metropolis) and rural areas (northeast region and Surin province) indicated that decreased growth of younger populations in urban areas caused a marked increase in migration of young generations as the labor force moved from rural to urban areas, especially after the 1990s. Statistics of the inter-regional migration census from the northeast to central regions also indicated that this population flow began to increase around the year 1990. The present trends of population aging and various socioeconomic situations in rural and urban areas in Thailand will result in acceleration of population aging in rural areas through deprivation of rural young populations by urban areas.
Examples of demographic transition include transitions from high-fertility-high-mortality to high-fertility-low-mortality and to low-fertility-low-mortality. In general, a high population growth rate is observed in the high-fertility-low-mortality phase, and the rate of population growth decreases in the low-fertility-low-mortality phase. Using available demographic data from the Kingdom of Tonga for the years 1891 to 2011, we described the demographic transition pattern in this country. Since 1953, the crude mortality rate has been lower than 10‰, while the crude birth rate remained as high as 27‰ until 2011. Despite the high fertility and low mortality rates from 1996 to 2006, the mean annual population growth rate was only 4.2‰, which is attributable to the net migration rate of-17.8‰. In addition, out-migration of both young and older adults, together with the high fertility rate, contributed to the maintenance of the pyramidal shape of the population age structure of the country from 1956 to 2006. This study shows that this MIRAB (migration, remittance, aid financed, and bureaucracy) society, has been experiencing a unique demographic transition due to a high out-migration rate. Because the international migration rate has been increasing in various regions throughout the world, we may need to re-examine the demographic transition theory while considering the significant effects of international migration.
The Health and Demographic Surveillance System (HDSS) is a periodic follow-up survey platform that monitors population changes in areas that lack reliable civil registration systems. Based on the data from the HDSS program, started in two areas in Lao PDR in 2010, this paper examines the dynamics of a remote rural population (Xepon) in comparison with that of the population in an agriculturally developing area (Lahanam). According to our analysis, high fertility and high child mortality rates were the main features of the population of Xepon : the total fertility rate (TFR) was 4.5 ; the infant and under-5 mortality rates remained as high as 69.8 and 95.6, respectively, per 1000 live births ; and the average life expectancy was 62.1 years. In contrast, data from Lahanam reflected a demographic transition, with an average life expectancy of 63.9 years and a TFR of 1.3. If the TFR follows the trend found in Lahanam, which is associated with the increased use of contraceptives, it is projected that the population of Xepon will decrease and age within 50 years. This kind of demographic transition is to be expected in the not so distant future.
During the 20th century, Japanese society experienced dramatic demographic changes accompanied by shifts in the epidemiological and health-related domains. During this demographic transition, mortality rates have declined, life expectancy has increased, and fertility rates have declined. Since 2008, the population has decreased and is expected to continue decreasing, with a higher average age. These changes are associated with shifts in the distribution of employment opportunities ; in the composition of households ; and in the balance between rural and urban populations, in favor of the latter, with jobs moving from the agricultural sector to manufacturing and service industries. Lifestyles have changed, social bonds have weakened, and the economic gap between generations and genders has increased. These changes have challenged society's ability to provide adequate and financially sustainable medical and nursing services while also reducing the potential environmental burden on future generations. The close relationship between demographic and social changes underlying this transition renders it difficult to mitigate the effects of future aging and shrinking of the Japanese population. Indeed, to develop strategies for the post-transition reality, various scenarios related to the population dynamics of the future must be examined. To this end, we suggest replacing the concept of chronological age with one of biological and societal age. Biological age can be represented by life-expectancy-equivalent age or by healthy life-expectancy-equivalent age, and societal age can be represented by age-structure-equivalent age. A healthy aging population should be promoted by developing sound relations between health and the natural, man-made, and societal environment.