• Stefan Rayer, Ph.D.

The 2005–2009 American Community Survey (ACS) county-to-county migration files, released in March 2012 by the U.S. Census Bureau, provide the first county-to-county migration flow tables since Census 2000. For small areas such as counties migration plays a major role in population change; often dwarfing the role of fertility and mortality. As such, the 2005–2009 ACS migration files provide an important snapshot of recent population changes impacting Florida counties.

The ACS migration data are not directly comparable to those derived from the decennial census long form in the past. In censuses up to the year 2000, respondents were asked where a person lived five years ago, and the county-to-county migration flow files referenced that five year period. In contrast, in the ACS a “county-to-county flow pair consists of the county of current residence at the time the ACS was conducted and the county of residence 1 year before then. The number of county-to-county movers is the estimated number of people age 1 year and over who moved between the county pair in a typical 1 year interval within the period 2005–2009. The county-to-county flow pairs and movers in the ACS 5-year estimates are not the summation of five years of data. Rather, the 2005–2009 ACS 5-year estimates are a yearly average for this time period.” (Benetsky and Koerber, 2012a: 10–11). Nevertheless, though the migration questions differ between the ACS and the decennial census, initial analyses indicate that there is congruence in the relative magnitude of county-to county movers (Benetsky and Koerber, 2012b).

The 2005–2009 ACS county-to-county migration files cover inflow-to and outflows-from each county in the United States. In this article, the ten largest inflows to Florida counties from counties in other states, the ten largest outflows from Florida counties to counties in other states, the ten largest inflows from abroad, and the largest within-Florida flows will be highlighted. The full dataset can be accessed through the U.S. Census Bureau’s website at http://www.census.gov

Domestic In-Migration

Table 1 shows the ten largest in-migration flows to Florida counties from counties outside the state of Florida. The table illustrates a remarkable geographic concentration of origin counties. All ten flows originated in New York State, and all but one (Nassau County, NY, to Palm Beach County, FL) were from three of the five boroughs of New York City (Brooklyn, Manhattan, and Queens). Not surprisingly, the destinations were the largest counties in Florida, with Palm Beach County receiving four of the largest domestic in-migration flows, Broward County three, Miami-Dade County two, and Orange County one.

Domestic Out-Migration

Table 2 documents that in contrast to migration flows to Florida counties from counties in other states, domestic out-migration from Florida counties was more geographically dispersed. Four of the ten largest out-migration flows were to two counties in the Atlanta metropolitan area in Georgia (Gwinnett and Fulton, GA). Other destinations with large flows included Houston (Harris County, TX), San Diego, Los Angeles, New York City/Manhattan (New York County, NY), Charlotte (Mecklenburg County, NC), and Chicago (Cook County, IL). All but one of the ten largest out-flows (Escambia County) originated in Miami-Dade and Broward counties. The Escambia County to San Diego County flow likely represents to a large extent personnel movement between the Naval Air Stations Pensacola and North Island.

In-Migration from Abroad

The ACS county-to-county migration files also include migration flows from abroad, with the places of origin aggregated to foreign regions; migration flows from the United States to other countries are not available. As can be seen in Table 3, Miami-Dade County was the primary destination in Florida for migrants from abroad. Migrants from the Caribbean region constituted the largest inflow by a wide margin, followed by migrants from South and Central America. Other counties in Florida with large inflows from abroad included Broward, Orange, and Palm Beach counties. The inflow to Orange County was unique in that it was dominated by Puerto Ricans (migrants from Puerto Rico also constituted the largest inflows from abroad in neighboring Lake, Osceola, and Seminole counties; data not shown). The “Northern America” foreign region in the ACS migration files represents largely Canadians; their migration to Broward County was the seventh largest inflow from abroad overall.

Within-Florida Migration

Migration exchanges between Florida counties represented the largest flows in general. In fact, except for migration from the Caribbean region to Miami-Dade County (Table 2), which was the second largest flow overall, the numerically largest flows all occurred within Florida (Table 4). Furthermore, all ten of the largest flows within Florida involved exchanges between geographically adjacent counties, with the Miami-Dade County to Broward County exchange constituting the largest flow by a wide margin. This shows that migration is first and foremost local in nature.