This study investigates the significance of India's emergence as the world's most populous nation in 2023, surpassing China, and its consequential implications for economic growth. With a focus on the demographic dividend driven by working-age and prime-age populations, we analyze the effects of shifting age distribution on India's labor force, labor market, and economic drivers. Extending the study period by integrating additional datasets, we examine per capita GDP growth, sectoral value-added, and employment shifts at the state level. Results reveal limited influence on per capita output, but significant sectoral effects. Notably, prime age composition within the working-age population emerges as a key driver of economic growth.