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    Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950-2019: a comprehensive demographic analysis for the Global Burden of Disease Study 2019

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    BACKGROUND: Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. METHODS: 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10-14 and 50-54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed age-specific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. FINDINGS: The global TFR decreased from 2·72 (95% uncertainty interval [UI] 2·66-2·79) in 2000 to 2·31 (2·17-2·46) in 2019. Global annual livebirths increased from 134·5 million (131·5-137·8) in 2000 to a peak of 139·6 million (133·0-146·9) in 2016. Global livebirths then declined to 135·3 million (127·2-144·1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2·1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27·1% (95% UI 26·4-27·8) of global livebirths. Global life expectancy at birth increased from 67·2 years (95% UI 66·8-67·6) in 2000 to 73·5 years (72·8-74·3) in 2019. The total number of deaths increased from 50·7 million (49·5-51·9) in 2000 to 56·5 million (53·7-59·2) in 2019. Under-5 deaths declined from 9·6 million (9·1-10·3) in 2000 to 5·0 million (4·3-6·0) in 2019. Global population increased by 25·7%, from 6·2 billion (6·0-6·3) in 2000 to 7·7 billion (7·5-8·0) in 2019. In 2019, 34 countries had negative natural rates of increase; in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58·6 years (56·1-60·8) in 2000 to 63·5 years (60·8-66·1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019. INTERPRETATION: Over the past 20 years, fertility rates have been dropping steadily and life expectancy has been increasing, with few exceptions. Much of this change follows historical patterns linking social and economic determinants, such as those captured by the GBD Socio-demographic Index, with demographic outcomes. More recently, several countries have experienced a combination of low fertility and stagnating improvement in mortality rates, pushing more populations into the late stages of the demographic transition. Tracking demographic change and the emergence of new patterns will be essential for global health monitoring. FUNDING: Bill & Melinda Gates Foundation

    The demographics of global corporate champions

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    This Working Paper presents a novel dataset documenting the demographics of the worldâ??s 500 largest companies by market capitalisation.The data illustrate a stark contrast between the main global economic regions. In Europe and Japan, large companies tend to be fairly old. In the United States, older champions coexist with a significant number of new ones. In emerging economies, most champions were born in the second half of the 20th century and reflect a rapid catch-up growth process.

    Demographics of Transition Objects

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    The unusual properties of transition objects (young stars with an optically thin inner disc surrounded by an optically thick outer disc) suggest that significant disc evolution has occured in these systems. We explore the nature of these systems by examining their demographics, specifically their stellar accretion rates (Mdot) and disc masses (Mdisc) compared to those of accreting T Tauri stars of comparable age. We find that transition objects in Taurus occupy a restricted region of the Mdot vs. Mdisc plane. Compared to non-transition single stars in Taurus, they have stellar accretion rates that are typically ~10 times lower at the same disc mass and median disc masses ~4 times larger. These properties are anticipated by several proposed planet formation theories and suggest that the formation of Jovian mass planets may play a significant role in explaining the origin of at least some transition objects. Considering transition objects as a distinct demographic group among accreting T Tauri stars leads to a tighter relationship between disc masses and stellar accretion rates, with a slope between the two quantities that is close to the value of unity expected in simple theories of disc accretion.Comment: 11 pages, 4 figures, to appear in MNRA

    Competition and demographics

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    Mainstream economics views demographic changes in the structure of households as of little relevance for the behavior of firms or the functioning of markets. The present paper dispels this view by arguing that changes in the number of non-workers could affect the intensity with which consumers search for best prices and therefore the level of competition. The author also analyzes the relationship between income and competition, which some studies suggest is negative. The author argues that the negative relationship is most likely due to the demographic factors discussed.Markets and Market Access,Education for Development (superceded),Economic Theory&Research,Labor Policies,Emerging Markets

    Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries

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    Background Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019

    Comparing Simple Quasar Demographics Models

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    This paper explores several simple model variations for the connections among quasars, galaxies, and dark matter halos for redshifts 1 < z < 6. A key component of these models is that we enforce a self-consistent black hole (BH) history by tracking both BH mass and BH growth rate at all redshifts. We connect objects across redshift with a simple constant-number-density procedure, and choose a fiducial model with a relationship between BH and galaxy growth rates that is linear and evolves in a simple way with redshift. Within this fiducial model, we find the quasar luminosity function (QLF) by calculating an "intrinsic" luminosity based on either the BH mass or BH growth rate, and then choosing a model of quasar variability with either a lognormal or truncated power-law distribution of instantaneous luminosities. This gives four model variations, which we fit to the observed QLF at each redshift. With the best-fit models in hand, we undertake a detailed comparison of the four fiducial models, and explore changes to our fiducial model of the BH-galaxy relationship. Each model variation can successfully fit the observed QLF, the shape of which is generally set by the "intrinsic" luminosity at the faint end and by the scatter due to variability at the bright end. We focus on accounting for the reasons that physically different models can make such similar predictions, and on identifying what observational data or physical arguments are most essential in breaking the degeneracies among models.Comment: 14 pages, 8 figures, 1 tabl

    Demographics in demand systems

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    Household composition can be expected to affect the allocation of household expenditure among goods, at the very least because of economies of scale as household size increases and because different people have different needs (adults versus children, for example). Specifying demographic effects correctly in demand analysis is important both in order to estimate correct price and expenditure elasticities and for the purpose of making household welfare comparisons. A common way of including demographics is as a function that scales total expenditure, and to make this scaling function indepen- dent of the level of total expenditure. A popular method in the parametric estimation of demand systems is to estimate share equations that are quadratic in the logarithm of total expenditure, but there is also a substantial literature on the semi-parametric estimation of Engel curves. We employ some of these semi-parametric techniques to show that, for some goods, further terms are likely to be required in the Engel curve addition to quadratic terms. We use this to identify the parameters of a scaling function that varies with total expenditure. Keywords: Demand analysis, demographics, base independence, semi-parametric.Demand analysis, demographics, base independence, semi-parametric
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