Did you know? Each year the IRS Statistics of Income (SOI) division analyses the addresses on all foreign and domestic tax returns to identify and quantify migration flows throughout the country. The IRS uses the social security number of the primary tax filer to match each tax return to a return from the previous year. If the address on last year’s return is in a different county, state, or country then the filer is identified as a migrant.
The IRS includes two kinds of migration flows: in-migrants who have moved in to counties since the previous year, and out-migrants who have moved out of counties since the previous year. PolicyMap has chosen to map in-migration, out-migration, and net-migration. The net-migration is calculated by subtracting out-migrants from in-migrants.
In addition to counting the total number of returns associated with migrants, the IRS also includes the total number of exemptions on migrant returns. The number of exemptions is a proxy for the number of members in the household. In short, the number of returns is used to estimate households, and the number of exemptions reported on these returns is used to estimate individuals.
PolicyMap now has all this county migration data available free to all visitors under the Demographics > Migration tab. Under the migration tab you’ll find in-flow, out-flow, and net-flow data on migrant households and migrant populations. Try out the interactive map below, or visit policymap now to see what’s happening in your county!