New Delhi, July 20 -- Indian policymakers recently renewed an old call: move workers out of agriculture. It is good economics-the traditional path to prosperity involves a country's labour force moving from farms to manufacturing and then to services. Except that in India, that transformation is already done to a large extent, at least among the young.

Such calls today ignore what has happened to the age structure of those employed on farms and what will happen if we push more people off them.

The median age of a farm worker in India in 2025 was 40 years. It has increased by five years over the last two decades. In some states, farm workers are even older. A typical farm worker in Kerala was 53 years old; and in Tamil Nadu and West Beng...