Demographic dividend occurs when the proportion of working people in the total population is high.
This indicates that more people have the potential to be productive and contribute to growth of the economy.
According to the United National population research, during the last four decades the countries of Asia and Latin America have been the main beneficiaries of the demographic dividend.
Advanced countries of Europe, Japan and USA have an ageing population because of low birth rates and low mortality rates.
Falling birth rates reduce the overall expenditure required to provide basic necessities for the under 14 age group (which is yet to be productive)
Increased longevity ensures that a large proportion of the population are within the 15-59 age group (working population).
Dependency ratio refers to the proportion of non -working poplation on the working population.
In India this ratio is around 0.6 according to the World Bank.