India is projected to overtake China as the world's most populous country by the end of this month when its population is expected to reach 1.425 billion, according to the United Nations.

India's population is projected to stabilise after the year 2064 and will be around 1.5 billion at the end of the century, a senior UN official said on Monday.

"India is projected to overtake China as the world's most populous country during the current month - April of 2023. Chinese population reached its peak size of 1.4 billion in 2022, and has begun to decline,” Director, Population Division, UN Department of Economic and Social Affairs (DESA) John Wilmoth said at a news briefing here.

Wilmoth said that projections indicate that the size of the Chinese population could drop below 1 billion before the end of the century.

"In India, by contrast, the population is expected to continue growing for several decades,” he said.

According to the forecast based on the latest United Nations estimates and projections of the global population released on Monday, India will dethrone China as the world’s most populous nation by end of this month when its population is expected to reach 1.425 billion.

In response to a question by PTI, Senior Population Affairs Officer, Population Division, DESA Sarah Hertog said that the agency’s medium projection indicates that India's population could stop growing around 2064 and stabilise thereafter.

She, however, cautioned that there is some uncertainty around that projection.

“We project that the population of India will be around 1.5 billion at the end of the century in the medium period,” Hertog said.

Last week, the United Nations Population Fund (UNFPA) said in its State of World Population report “8 Billion Lives, Infinite Possibilities: the case for rights and choices” that India will become the world’s most populous nation by mid-year 2023 when its population will be 1.428 billion, surpassing China's 1.425 billion people.

The policy brief released on Monday states that India’s population will overtake that of China this month.

Responding to a question on the differing projections by two UN agencies on when India will surpass China as the world’s most populous nation, Wilmoth said it is “unfortunate” that the communication is not clear.

“The main point is that it (India overtaking China in population) is happening during this year. There's also a great deal of uncertainty around this estimate. The precise timing of when this crossover occurs is not known for sure and it will never be known,” he said.

Wilmoth said that estimates of the timing of the crossover will probably be revised when the UN receives the next census from India in 2024.

“We will certainly go back and redo all of these calculations and I'm sure the date is going to change. It will not be April 2023. That would be my prediction,” he said. India’s planned 2021 census was delayed due to challenges posed by the Covid-19 pandemic and is now scheduled for 2024.

In China, the most recent census was done in November 2020.

UN DESA noted that due to the uncertainty associated with estimating and projecting populations, the specific date on which India is expected to surpass China in population size is approximate and subject to revision.

Wilmoth added that the main driver of the population trends in India and China is the fertility level in the two populations.

“In 2022, China had one of the world's lowest fertility rates, which was 1.2 births per woman on average over a lifetime. India's current fertility rate, which is at 2.0 births per woman, is just below the replacement threshold of 2.1 which is the level required for population stabilisation in the long run in the absence of migration,” he said.

On the economic and social implications of the population crossover between India and China, Wilmoth said: “While the crossover per se may have little importance on its own, what matters is the underlying trends that have produced the crossover.” He said between 2023 and 2050, the number of persons aged 65 or over is expected to nearly double in China and to increase by more than double in India.

He said that these trends call attention to the challenges of providing social support and protection to growing numbers of older persons.

The UN DESA policy brief adds that as a proportion of the total population, the growth of the older population in India will be much slower than in China.

Wilmoth said the trends that underlie the population crossover are linked to the demographic dividend, which is a boost in economic growth driven by an increase in the size of the working-age population as a share of the total.

“This benefit is time-bound, but its duration and intensity vary across countries depending in particular on the steepness of the fertility decline that they experience,” he said.

In India, the number of adults of working age is projected to continue increasing both in number and as a proportion of the total population through mid-century, providing opportunities for faster economic growth over the next few decades.

Meanwhile, in China, projections indicate that the percentage of the population at ages 25-64 will peak in the coming years, closing the window of opportunity created by the changing age distribution.

The UN agency said the policies and programmes aimed at influencing fertility should ensure the basic human right of all individuals and couples to decide freely and responsibly on the number and the timing of their children and to have the information and means to do so.

Employment and social policies need to make it both possible and desirable for women to have children while remaining in the labour market and continuing to develop their careers. Such policies can include the provision of subsidised childcare, maternal and paternal leave, and tax credits, among others.

Wilmoth said the working-age population in India is expected to reach a peak at around 2045.

India is in “its period of the so-called demographic dividend in the sense that it's still experiencing an increase in the relative size of the working-age population. So this has a positive impact overall on economic growth per capita,” he said.

But, he noted, that the size of the workforce is what really matters and not just the number of people of working age.

“It's not just the number of people in the working age range, but it's also whether they're engaged, and it's also how well educated they are, therefore how productive they are in terms of contributing to the economy.

“The demographic change is only one piece of it. I think sometimes there's a lot made out of this demographic dividend, but it's really only one piece of the puzzle in terms of what contributes to economic growth and what can help countries,” he said.

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