In fact, some scholars of the Indian economy are estimating a growth-rate crossover before 2020: when the Indian economy averages higher economic growth than China. And no scholars can usefully estimate political outcomes – how rapidly can India solve its governance problems?
The relative demographics are huge. China has been benefiting from a bulge of working-age adults. That beneficial trend is now rapidly being reversed as the above charts indicate. Conversely, India is just beginning to benefit from a working-age bulge, which will be smoother and longer-lasting than China’s experience.