has traditionally been low, but recent evidence from the 2011 Census suggests the annual rate of growth of labor migrants nearly doubled relative to the previous decade, rising to 4.5 percent per annum between 2001 and 2011, from 2.4 percent during the previous decade. Therefore, the stock of migrants stating economic reasons for migration increased to 51 million in 2011; over 80 percent of these migrants were male. The increasing importance of economic reasons for migration over time is also reflected in the NSSO household surveys. In 1992–93, 41.5 percent urban male migrants cited economic reasons for migration, compared to 51.9 percent in 1999–2000 and 55.7 percent in 2007–08.

The CMM, based on Census data, estimates a much larger stock of labor-related migrants compared to traditional estimates. This metric, developed in the Government of India’s recent Economic Survey, considers net migration to be the percentage change in population between the 10-19-year-old cohort in an initial census period and the 20-29-year-old cohort in the same area (state or district) a decade later, after correcting for mortality effects. It is likely to capture labor migration, as other bilateral movements for reasons such as marriage are netted out. According to this metric, the stock of all the out-of-state net migrants in the 20-29 age cohort between 2001 and 2011 exceeded 11 million people, up from around 6 million people during the previous decade. And nearly 80 percent of these migrants were male in both periods. The 20-29 age cohort formed a fifth of all migrants who moved for economic reasons. Therefore, using a scaling factor of five, the number of out-of-state net (labor) migrants between 2001 and 2011 can be estimated at over 55 million people. The stock of all economically motivated inter-district migrants is similarly estimated at over 80 million.

The India Human Development Survey (IHDS) is another source of data that provides an appropriate sample to analyze internal migration for economic reasons. This is attributable to migrant husbands being the dominant stream. Based on the IHDS, nonresident household members are identified through household responses to the following questions: (a) Does any woman/man in the household have a husband/wife who lives outside the household? (b) Is there any household member who has children studying outside the household? and (c) Do any children under the age of 15 in the household have parents who live outside the household? Migrant husbands are the dominant category, accounting for almost half of all nonresident household members in 2011-12. Nonresident students were the other major category, with a share of almost 40 percent in 2011-12. Migrant parents and migrant wives each had small shares and this distribution of the “type” of migration was not very different in 2004-05 compared to 2011-12 (Figure 3).

Comparing estimates of internal migration based on the IHDS with those from other data sources, however, is far from straightforward. The IHDS, which defines migrants as the stock of nonresident household members, estimates that 11.5 percent of households (4,761 of a total 41,554 households) had at least one nonresident family member in 2004-05. This share doubled to 24 percent in 2011-12. As a share of the population, nonresident household members increased from 2.4 percent in 2004-05 to 6.5 percent in 2011-12. Comparing these estimates with internal migration rates from other data sources – 30.1 and 28.5 percent of the country’s population, respectively, from the 2001 Census and the 2007-08 NSSO household survey – however, is a case of comparing apples and oranges. The IHDS does not capture (a) women who migrate primarily for marriage, (b) individuals who migrate to join the earning member of the family, and (c) entire households that move together.

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