Nov. 9 (UPI) -- Global population growth is a tale of two statistics: In 104 countries with high birth rates, populations are rising, while rates in 91 countries with low numbers are sinking.
Since 1950, the total fertility rates, the average number of children a woman gives birth to during her lifetime, has fallen worldwide.
The statistics come from recent findings included in the annual Global Burden of Disease study.
Among the 104 nations with birth rates exceeding two births per woman were Niger, Mali, Chad and South Sudan. The 91 nations with fertility rates lower than two births per woman included Singapore, Spain, Portugal, Norway, South Korea and Cyprus.
To assess this divergent phenomenon, the annual study examined 84 risk factors in 195 countries and territories.
"These statistics represent both a 'baby boom' for some nations and a 'baby bust' for others," Christopher Murray, Director of the Institute for Health Metrics and Evaluation at the University of Washington, said in a press release. "The lower rates of women's fertility clearly reflect not only access to and availability of reproductive health services, but also many women choosing to delay or forgo giving birth, as well as having more opportunities for education and employment."
From 2007 to 2017, the world's population grew each year by about 87 million people, versus nearly 82 million each year from 1997 to 2007. In 1950, high-income countries made up 24 percent of the world's population. In 2017, the population of these countries accounted for only 14 percent.
The study also included some of the main risk factors for people around the globe. Among the leading causes of death were ischemic heart disease, neonatal disorders, stroke, lower respiratory infections, diarrhea, road injuries and chronic obstructive pulmonary disease. Each of those conditions caused more than 1 million deaths worldwide in 2017.
HIV, however, remains one of the major causes of death around the globe, and experts think eliminating the threat of new infections of the disease is unlikely.
"HIV remains a massive public health threat, particularly because global financing has plateaued, domestic health spending has stayed low among high-burden countries, and its incidence has not declined as quickly in younger as in older populations," Murray said.
"How best to galvanize accelerated action against HIV, as well as the world's other great health challenges, is far from clear. Going forward, the annual GBD study offers international agencies, nations' health officials, and other stakeholders a platform through which strategies and programs can be tested and analyzed."