India is projected to overtake China as the world's most populous country around 2027, a UN report said on Monday.
The world's population is expected to increase by two billion in the next 30 years, from 7.7 billion currently to 9.7 billion in 2050, said 'The World Population Prospects 2019: Highlights' published by the Population Division of the UN Department of Economic and Social Affairs.
It provides a comprehensive overview of global demographic patterns and prospects.
The study concluded that the world's population could reach its peak around the end of the current century, at a level of nearly 11 billion.
The new population projections indicate that nine countries will make up more than half the projected growth of the global population between now and 2050 - India, Nigeria, Pakistan, Congo, Ethiopia, Tanzania, Indonesia, Egypt and the US (in descending order of the expected increase).
The report also confirmed that the world's population is growing older due to increasing life expectancy and falling fertility levels, and that the number of countries experiencing a reduction in population size is growing.
The resulting changes in the size, composition and distribution of the world's population have important consequences for achieving the Sustainable Development Goals (SDGs), the globally agreed targets for improving economic prosperity and social well-being while protecting the environment.
The population of sub-Saharan Africa is projected to double by 2050 (99 per cent increase).
Regions that may experience lower rates of population growth between 2019 and 2050 include Oceania, excluding Australia and New Zealand (56 per cent), Northern Africa and Western Asia (46 per cent), Australia and New Zealand (28 per cent), Central and Southern Asia (25 per cent), Latin America and the Caribbean (18 per cent), Eastern and South-Eastern Asia (three per cent), and Europe and Northern America (two per cent).
The global fertility rate, which fell from 3.2 births per woman in 1990 to 2.5 in 2019, is projected to decline further to 2.2 in 2050.
In 2019, fertility remains above 2.1 births per woman, on average, over a lifetime in sub-Saharan Africa (4.6), Oceania excluding Australia and New Zealand (3.4), Northern Africa and Western Asia (2.9), and Central and Southern Asia (2.4).A fertility level of 2.1 births per woman is needed to ensure replacement of generations and avoid population decline over the long run in the absence of immigration.