Cohort-based Migration Metric (CMM)

A Cohort-based Migration Metric (CMM) is developed to gauge net migration at the state and district level.This metric 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 yearold cohort in the same area a decade later, after correcting for mortality effects.

• Internal migration rates have dipped in Maharashtra and surged in Tamil Nadu and Kerala reflecting the growing pull of southern states in India’s migration dynamics.
• Out-migration rates increased in Madhya Pradesh, Bihar and Uttar Pradesh and have dipped in Assam.
• Relatively less developed states such as Bihar and Uttar Pradesh have high net outmigration.
• Relatively more developed states take positive CMM values reflecting net inmigration: Goa, Delhi, Maharashtra, Gujarat, Tamil Nadu, Kerala and Karnataka.
• As per Census 2001, the 20-29 age cohort formed a fifth of all migrants and of all migrants who moved for economic reasons respectively.
• Another important development is the growing role of female migrants. Until the 2000s, migration was largely a male dominated phenomenon. But in the 2000s there was a marked shift in the distribution for females (indicating more outflows), indeed much more than the shift for males, consistent with the discussion in the section on Census data.