India's population may peak to 1.6 bn in 2048, decline in 2100 to 1.09 bn: Study

India's population will peak in 2048 at 1.6 billion, which will be followed by a 32% decline to around 1.09 billion in 2100, according to an analysis published in The Lancet. As per the study, India in 2100 will be the world’s most populous country. The world’s population will peak at 9.73 billion in 2064, it added.