Predicting the most populous country in the next 50 years can be challenging, as it depends on various factors including fertility rates, mortality rates, and migration trends. However, according to current UN predictions, India is expected to overtake China as the world's most populous country by 2027.

Predicting the most populous country in the next 50 years involves analyzing current demographic trends, fertility rates, aging populations, and government policies. Here’s the outlook based on projections:

Most Populous Country by 2074 (Next 50 Years)

1. India – Currently the most populous country (surpassing China in 2023), India is expected to remain #1 due to:
2. Higher fertility rates compared to China (though declining).
3. A large youth population driving growth for decades.

4. UN projections estimate ~1.6 billion people by 2050, likely peaking before 2074.

5. China – Will likely drop to 2nd place due to:

6. Rapidly declining birth rates (one of the world’s lowest fertility rates at ~1.0).
7. Aging population (over 30% aged 60+ by 2050).

8. Population expected to shrink to ~1.3 billion by 2050 and further by 2074.

9. Nigeria – Could become the 3rd most populous by 2074 due to:

10. High fertility rates (currently ~5.2 births per woman).

11. Rapid growth may push its population to ~400-500 million by 2074.

12. United States – May remain in the top 4 due to immigration and moderate fertility, but unlikely to surpass India or China.

Key Factors Affecting Future Population:

• Fertility Decline: Most countries (including India) are seeing slower growth as education and urbanization rise.
• Africa’s Growth: Nigeria, DR Congo, Ethiopia, and Tanzania will drive much of the world’s population increase.
• Aging Populations: China, Japan, and Europe will shrink due to low birth rates and aging societies.

Conclusion:

India will almost certainly remain the most populous country in 50 years, while China’s population shrinks and African nations rise in rank. Nigeria may challenge for 2nd place by the late 21st century.

Would you like specific UN/World Bank data references?