In 2020, the age dependency ratio in Tanzania was 85.9 percent. This meant that there were around 86 people aged 0-14 years and 65 years and older per 100 working-age population (aged 15-64 years). The ratio declined from 90 percent in 2000, indicating a reduced burden for the working-age population. Despite the decrease, the indicator was still higher than the average age dependency in Africa.

Objectives: To investigate the relationship between the Short Physical Performance Battery (SPPB) and the Study of Osteoporotic Fractures (SOF) index.Methods: We present data from a cross-sectional survey conducted in Cameroon. Frailty was defined as an SOF index > 0. The sensitivity and specificity of the SPPB were investigated. Principal component analysis (PCA) was performed to assess the contribution of each subtest of the SPPB to the relationship with the SOF.Results: Among 403 people included (49.6% women), average age of 67.1 (±6.2) years, 35.7% were frail according to the SOF. After determining the best SPPB threshold for diagnosing frailty (threshold = 9, Se = 88.9%, Sp = 74.9%), 47.9% were frail according to the SPPB. The first dimension of PCA explained 55.8% of the variability in the data. Among the subtests of the SPPB, the chair stand test item was the component most associated with the SOF index.Conclusion: Despite the overlap between the SOF and the SPPB, our results suggest that a negative result on the five chair-stands test alone would be sufficient to suspect physical frailty.

The median age of Germans in 2025 was 45.5 years, meaning that half the German population was younger, half older. Following some fluctuation during the post-WWII baby boom waves, Germany's average age has been on an upwards trajectory since the 1970s, with a sharp rise in the 1990s and 2000s, although it has slowed in recent years. It is projected to peak at over 48 years in the 2040s, before plateauing around the 47 year mark for the remainder of the century. Aging in Germany This shift in the age makeup of Germany is driven by having fewer young people and more old people. While it has increased slightly in the last decade, the German fertility rate remains low. Fewer young people lead to a higher median age, as does rising life expectancy. These trends have significant economic and societal impacts, where workforces shrink and the elderly population places greater demand on healthcare systems and public finances, while families must increasingly care for elderly relatives. Regional and global trends The entire European Union, due to higher levels of development, shows an upward shift in its age distribution. While this shift is occurring globally, the level of Germany’s median age is particularly high. In many other parts of the world, particularly Subsaharan Africa, the proportion of young and old inhabitants is skewed sharply toward the young, pulling the median age lower.

South Africa ZA: Age Dependency Ratio: % of Working-Age Population data was reported at 52.275 % in 2017. This records a decrease from the previous number of 52.409 % for 2016. South Africa ZA: Age Dependency Ratio: % of Working-Age Population data is updated yearly, averaging 75.926 % from Dec 1960 (Median) to 2017, with 58 observations. The data reached an all-time high of 85.403 % in 1966 and a record low of 52.275 % in 2017. South Africa ZA: Age Dependency Ratio: % of Working-Age Population data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s South Africa – Table ZA.World Bank: Population and Urbanization Statistics. Age dependency ratio is the ratio of dependents--people younger than 15 or older than 64--to the working-age population--those ages 15-64. Data are shown as the proportion of dependents per 100 working-age population.; ; World Bank staff estimates based on age distributions of United Nations Population Division's World Population Prospects: 2017 Revision.; Weighted average; Relevance to gender indicator: this indicator implies the dependency burden that the working-age population bears in relation to children and the elderly. Many times single or widowed women who are the sole caregiver of a household have a high dependency ratio.

Globally, about 25 percent of the population is under 15 years of age and 10 percent is over 65 years of age. Africa has the youngest population worldwide. In Sub-Saharan Africa, more than 40 percent of the population is below 15 years, and only three percent are above 65, indicating the low life expectancy in several of the countries. In Europe, on the other hand, a higher share of the population is above 65 years than the population under 15 years. Fertility rates The high share of children and youth in Africa is connected to the high fertility rates on the continent. For instance, South Sudan and Niger have the highest population growth rates globally. However, about 50 percent of the world’s population live in countries with low fertility, where women have less than 2.1 children. Some countries in Europe, like Latvia and Lithuania, have experienced a population decline of one percent, and in the Cook Islands, it is even above two percent. In Europe, the majority of the population was previously working-aged adults with few dependents, but this trend is expected to reverse soon, and it is predicted that by 2050, the older population will outnumber the young in many developed countries. Growing global population As of 2025, there are 8.1 billion people living on the planet, and this is expected to reach more than nine billion before 2040. Moreover, the global population is expected to reach 10 billions around 2060, before slowing and then even falling slightly by 2100. As the population growth rates indicate, a significant share of the population increase will happen in Africa.

In 2023, the population of Africa was projected to grow by 2.34 percent compared to the previous year. The population growth rate on the continent has been constantly over 2.3 percent from 2000 onwards, and it peaked at 2.59 percent between 2012 and 2013. Despite a slowdown in the growth rate, the continent's population will continue to increase significantly in the coming years. The second-largest population worldwide In 2022, the total population of Africa amounted to around 1.4 billion. The number of inhabitants had grown steadily in the previous decades, rising from approximately 810 million in 2000. Driven by a decreasing mortality rate and a higher life expectancy at birth, the African population was forecast to increase to about 2.5 billion individuals by 2050. Africa is currently the second most populous continent worldwide after Asia. However, forecasts showed that Africa could gradually close the gap and almost reach the size of the Asian population in 2100. By that year, Africa might count 3.9 billion people, compared to 4.7 billion in Asia. The world's youngest continent The median age in Africa corresponded to 18.8 years in 2023. Although the median age has increased in recent years, the continent remains the youngest worldwide. In 2023, roughly 40 percent of the African population was aged 15 years and younger, compared to a global average of 25 percent. Africa recorded not only the highest share of youth but also the smallest elderly population worldwide. As of the same year, only three percent of Africa's population was aged 65 years and older. Africa and Latin America were the only regions below the global average of 10 percent. On the continent, Niger, Uganda, and Angola were the countries with the youngest population in 2023.

In 2023, just under 42 percent of Sub-Saharan Africa's population was below the age of 15; in contrast, this figure was just 18 percent in Europe & Central Asia and in North America. Across these regions, the share of the population aged 65 and over inversely correlated with the younger population, in that the regions with the largest share aged under 15 had the smallest share aged over 64, and vice versa. For most regions, the share of the population aged between 15 and 64 years ranged between 64 and 65 percent, except for Sub-Saharan Africa where it was below 56 percent. These trends can largely be explained by looking at global demographic development.

As of 2024, South Africa's population increased, counting approximately 63 million inhabitants. Of these, roughly 27.5 million were aged 0-24, while 654,000 people were 80 years or older. Gauteng and Cape Town are the most populated South Africa’s yearly population growth has been fluctuating since 2013, with the growth rate dropping below the world average in 2024. The majority of people lived in the borders of Gauteng, the smallest of the nine provinces in terms of land area. The number of people residing there amounted to 16.6 million in 2023. Although the Western Cape was the third-largest province, the city of Cape Town had the highest number of inhabitants in the country, at 3.4 million. An underemployed younger population South Africa has a large population under 14, who will be looking for job opportunities in the future. However, the country's labor market has had difficulty integrating these youngsters. Specifically, as of the fourth quarter of 2024, the unemployment rate reached close to 60 percent and 384 percent among people aged 15-24 and 25–34 years, respectively. In the same period, some 27 percent of the individuals between 15 and 24 years were economically active, while the labor force participation rate was higher among people aged 25 to 34, at 74.3 percent.

Nigeria's population structure reveals a youthful demographic, with those aged **** years comprising the largest age group compared to the total of those between the ages of 30 and 84 years. The majority of the young population are men. This demographic trend has significant implications for Nigeria's future, particularly in terms of economic development and social services. It has the potential to offer a large future workforce that could drive economic growth if it is adequately educated and employed. However, without sufficient investment in health, education, and job creation, this youth bulge could strain public resources and fuel unemployment and social unrest. Poverty challenges amid population growth Despite Nigeria's large youth population, the country faces substantial poverty challenges. This is largely due to its youth unemployment rate, which goes contrary to the expectation that the country’s large labor force would contribute to employment and the economic development of the nation. In 2022, an estimated **** million Nigerians lived in extreme poverty, defined as living on less than **** U.S. dollars a day. This number is expected to rise in the coming years, indicating a growing disparity between population growth and economic opportunities. The situation is particularly dire in rural areas, where **** million people live in extreme poverty compared to *** million in urban centers. Linguistic and ethnic diversity Nigeria's population is characterized by significant linguistic and ethnic diversity. Hausa is the most commonly spoken language at home, used by ** percent of the population, followed by Yoruba at ** percent and Igbo at ** percent. This linguistic variety reflects Nigeria's complex ethnic composition, with major groups including Hausa, Yoruba, Igbo, and Fulani. English, the country's official language, serves as the primary language of instruction in schools, promoting literacy across diverse communities.