Introduction

In April 2026, Common Sense Institute reported Iowa’s population grew from 2024 to 2025, though growth was slow and narrowly distributed. The state’s net increase of 7,900 residents over the year translates to a 0.25% growth rate, or half the national rate of 0.52%. The gains also rested on a narrow demographic base of net positive international migration. International migration carried the bulk of the state’s growth, while natural increase through births continued its long-run decline and net domestic migration contributed comparatively little.

This report takes a more granular look at Iowa’s population trends by exploring county-level data. It maps which of Iowa’s 99 counties gained and lost residents in 2025, places the most recent year in a 25-year context, and disaggregates the results by degree of rurality using the U.S. Department of Agriculture’s Rural-Urban Continuum Codes.[1] The report then decomposes county-level population change into its three demographic components—net births, net domestic migration, and net international migration. It ends with an analysis of who is moving into and out of metro and nonmetro Iowa using American Community Survey microdata. The data tells a tale of two Iowas: a metropolitan core that continues to grow through  all three demographic components, and a nonmetro periphery that depends almost exclusively on international migration for population growth.

Key Findings

• Between 2001 and 2025, nonmetro and rural Iowa counties never posted positive net domestic migration in aggregate for any year except for 2021. Only metro Iowa has positive net domestic migration flows (figure 8).
• In aggregate, international migration was the only positive contributor to population change across nonmetro and rural Iowa from 2022 to 2025 (figure 8).
• Natural increase (births minus deaths) has fallen in metro Iowa. Net births in metro counties fell from a 2007 peak of 11,492 to roughly 4,400 in 2025—a 60.2% decline (figure 7). A majority of Iowa’s 99 counties recorded more deaths than births in 2025.
• Iowa’s metro counties added 368,094 residents on net between 2001 and 2025, while the state’s nonmetro and rural counties combined lost approximately 109,000. Metro Iowa added population in every year of the 25-year period (figure 6).
• Only 42 of Iowa’s 99 counties gained population in 2025—and the growing counties cluster in and around the state’s metropolitan areas. The remaining 57 counties lost residents (figure 1).
  • Three counties grew by 1% or more in 2025: Dallas (3.2%), Wayne (1.6%), and Warren (1.5%). Nine counties contracted by at least 1%, led by Clay County with a 1.9% population decline.
• Iowa’s metro-driven net population growth reflects an exodus of higher-educated, higher-earning mid-career residents in exchange for lower-earning or unemployed young residents with less education moving in (figure 9).
  • While nonmetro Iowa is experiencing net population decline, its in-migrants, by contrast, are more economically established than the residents moving out (figure 10).

A Minority of Counties Drove Iowa's 2025 Growth

In its April 2026 report, “Population and Prosperity: Iowa’s Demographic Trends,” CSI reported Iowa’s population grew by nearly 7,900 residents in 2025 using newly released Census Bureau estimates.[2] However, a single statewide number hides the uneven distribution of that growth. Iowa's population change in any given year reflects very different patterns across its 99 counties. Some counties gain residents at rates well above the state average while others contract at rates that, sustained over a decade, can materially reshape local economies. Disaggregating data to the county level identifies where growth is occurring, where it is not, and which communities face the demographic headwinds that drive downstream fiscal and economic pressures.

According to the Census Bureau's Vintage 2025 estimates, Iowa's population growth was concentrated in a minority of counties in 2025.[3] Figure 1 maps the percent change in total population by county between July 1, 2024, and July 1, 2025.

Figure 1. 

Source: U.S. Census Bureau

In 2025, only 42 Iowa counties experienced population growth. Just three counties grew by 1% or more. Both on the outskirts of the Des Moines metropolitan area, Dallas County grew by 3.2% and Warren County by 1.5%. The third, Wayne County, grew 1.6% year-over-year despite a population of only about 6,700. Among the remaining 39 counties with positive population growth, 12 grew between 0.5% and 1%, and 27 grew by 0.5% or less.

The remaining 57 Iowa counties experienced a net decline in residents. Nine counties contracted at least 1%. Clay County led the decline at -1.9%, followed by Pocahontas (-1.5%), Louisa (-1.4%), Cherokee (-1.3%), Floyd (-1.2%), Franklin (-1.1%), Page (-1.0%), Humboldt (-1.0%), and Kossuth (-1.0%). Among the remaining counties that lost population, 19 contracted between 0.5% and 1%, and 29 contracted by 0.5% or less.

The concentration of population growth in a minority of counties is not unique to 2025. Figure 2 places the latest year of data in a longer-run context. The figure compares the number of Iowa counties with positive and negative year-over-year population growth in selected years since 2005. This figure illustrates whether the 2024–2025 distribution reflects common demographic patterns or not.

Figure 2. 

Source: U.S. Census Bureau

A majority of Iowa's 99 counties lost population in every benchmark year shown. The number of counties posting population growth ranged from 26 in 2020 to 42 in 2025, while the number of counties contracting ranged from 57 to 73. The 2020 estimate marked the widest margin in the series due to pandemic-era disruptions to net births and migration. The 2025 estimate represents the lowest margin, where 42 counties recorded growth. The number of counties with year-over-year population growth increased 62% from 2020 to 2025. This latest year of data also marks the most favorable distribution of population gains recorded in any benchmark year since 2005.[*] But despite this improvement, 57 counties still lost residents in 2025. These losses are not distributed randomly across the state. Iowa's growing counties cluster in and around its metropolitan areas, while the counties losing residents concentrate in the nonmetro and rural areas. Therefore, to better capture trends by region type, the following sections disaggregate counties by their degree of rurality.

Metro counties contribute most to population growth

The county-level map in the previous section suggested Iowa’s growing counties tend to sit in or near its metropolitan areas. This section tests that observation directly. It first compares 2025 growth across metro and nonmetro counties, then disaggregates Iowa’s 99 counties along the U.S. Department of Agriculture’s rural-urban continuum to show how growth varies with both population size and metro adjacency.[4] The data encompasses the past quarter century.

A glance at figure 1 suggests proximity to a metropolitan area contributes to whether an Iowa county gained or lost residents in 2025. To verify this observation, figure 3 plots county-level population growth by whether the county is located within a metro area or not.  The figure draws on Census Bureau data to clarify whether growing counties are concentrated inside metro areas or spread across both groups. Each dot represents one county, and the shaded distributions show where counties in each group cluster.

Figure 3. 

Source: U.S. Census Bureau, U.S. Department of Agriculture

According to figure 3, Iowa’s population growth was concentrated in metro counties in 2025. The median year-over-year population growth rate was 0.30% in metro-area counties, compared with -0.26% in nonmetro counties. A binary metro/nonmetro split, however, obscures meaningful variation within nonmetro Iowa. A county of 20,000 residents bordering the Des Moines metro faces different demographic prospects than a county of 5,000 in the state’s rural interior. Grouping the two together can mask the gradient between them. Capturing that gradient requires a finer classification.

The U.S. Department of Agriculture's Rural-Urban Continuum Codes (RUCC) provide a standard framework for the disaggregation of population growth data by county. The RUCC system assigns each U.S. county one of nine codes based on metropolitan status, population size, and adjacency to a metropolitan area. This code system allows analysts to distinguish between, for example, a small county next to Des Moines and a small county in the state's rural interior. Common Sense Institute condenses the nine RUCC codes into four broader categories used throughout this report. Metro counties (RUCC 1–3) belong to a metropolitan area. Nonmetro counties adjacent to a metro area (RUCC 4, 6, 8) sit outside a metropolitan area but border a metro county. Nonmetro counties not adjacent to a metro area (RUCC 5, 7) contain a town of at least 5,000 residents but do not border a metro county. Rural counties (RUCC 9) contain no town of at least 5,000 residents and do not border a metro area. Figure 4 shows the share of Iowa counties in each RUCC category that posted positive population growth in 2025.

Figure 4. 

Source: U.S. Census Bureau, U.S. Department of Agriculture

The 2025 growth distribution divides sharply along metro status. Among metro counties, 77% grew from 2024 to 2025—more than twice the rate of any nonmetro tier. Growth falls off steeply outside the metros: 35% of nonmetro counties adjacent to a metro area grew, compared with 26% of nonmetros not adjacent to a metro and 33% of the most rural counties. Metropolitan status is associated with substantially higher rates of county-level growth. This relationship holds across population-size tiers. Figure 5 extends this view across time. The figure disaggregates Iowa's annual total population change from 2001 to 2025 by the four condensed RUCC categories, showing year-over-year change alongside a five-year moving average for each tier.

Figure 5. 

Note: The gray line indicates the five-year average.
Source: U.S. Census Bureau, U.S. Department of Agriculture

Iowa's population growth has clustered in metropolitan and metro-adjacent counties for at least a quarter century, while most nonmetro counties have lost residents over the same period. Metro counties added population in every year of the 2001–25 period, with annual gains ranging from 8,857 to 21,714 residents, not including 2020. The five-year moving average peaked at over 19,000 in the early 2010s, declined through the late 2010s and early 2020s, and has since recovered to roughly 12,000 in 2025. Even at its weakest, metro Iowa never posted a year of net loss.

The three nonmetro tiers tell a different story. Nonmetro counties adjacent to a metro area posted modest losses in most years, with annual change oscillating between -1,857 and +471 residents. The five-year moving average has remained negative across nearly the entire 25-year window, briefly touching zero in the late 2000s before resuming its decline. Nonmetro counties not adjacent to a metro area performed worse, with annual losses typically between 448 and 4,386 residents and a five-year average that has not crossed into positive territory at any point in the series. Rural counties posted the largest absolute losses, exceeding 3,600 residents annually in the early 2000s and again in the late 2000s, before moderating to under 1,000 in recent years.

The rural-urban divide visible in the 2025 county map is not a recent development. It is the cumulative outcome of a 25-year pattern in which metro Iowa has grown every year and nonmetro Iowa has shrunk in nearly every year. In recent years, rural counties have seen a narrowing of losses but not a reversal; the moving average remains below zero across all three nonmetro tiers. And despite recent improvements, the cumulative magnitude of this divergence over the last 25 years is substantial.

Figure 6 plots the running sum of annual population change by RUCC tier from 2001 to 2025, converting the year-over-year fluctuations in figure 5 into a stock measure of net gain or loss over the full period.

Figure 6.

Source: U.S. Census Bureau, U.S. Department of Agriculture

Iowa's metro counties added 368,094 residents on net between 2001 and 2025. Over the same window, nonmetro counties adjacent to a metro area lost 18,197 residents, nonmetro counties not adjacent to a metro area lost 41,599, and rural counties lost 48,937. Indeed, the three nonmetro tiers combined shed approximately 109,000 residents over the 25-year period even as the total state population grew.

Total population change at the county level reflects the sum of three demographic components—net births, net domestic migration, and net international migration—each of which responds to different economic and policy conditions. The next section disaggregates Iowa's population change into these three components and examines how their relative contributions have shifted across rurality tiers.

Post-Pandemic Population Gains Depend Largely on International Migration

County-level population change reflects the sum of three demographic components: net births, net domestic migration, and net international migration. The net births datapoint equals new births minus deaths that year. Net domestic migration represents residents moving in minus residents moving out, including movement between U.S. states and movement between counties within Iowa. Finally, net international migration counts residents arriving from abroad minus those departing. Each component responds to different conditions. Net births responds to age structure, fertility trends, and mortality. Net domestic migration generally responds to factors like relative economic opportunity, housing costs, and quality-of-life factors. Net international migration is highly sensitive to federal immigration policy and employer demand for foreign-born labor. Disaggregating Iowa's population change into these three components reveals which forces contribute most to the rural-urban divide identified in the previous section. Figure 7 plots the annual contribution of each component to population change by RUCC tier from 2001 to 2025.

Figure 7. 

Source: U.S. Census Bureau

Three patterns stand out. First, net domestic migration has remained negative across all three nonmetro tiers in nearly every year of the series. These domestic migration figures capture both Iowans relocating across county lines and Iowans leaving the state altogether, as well as the corresponding inflows. For example, a resident of a rural county moving to a metro county would count as negative domestic migration for the rural county and positive for the metro county. In absolute terms, the rural and nonmetro tiers experienced the largest population losses from domestic migration. Net domestic outflows have averaged just under 2,000 residents per year in these tiers. Even in metro counties, however, net domestic migration has narrowed in recent years. Domestic migration in the metro tier averaged roughly 2,600 in the pre-pandemic years but only 1,200 since 2020.

Net births—historically the largest positive contributor across all four tiers—has collapsed in Iowa over the past decade. In the rural tier, net births fell from positive territory in the early 2000s to roughly zero or negative in most years since 2015, falling from an average of -228 in the pre-pandemic period to -730 since 2020.  Though less pronounced, the same pattern appears in the nonmetro-adjacent and nonmetro-not-adjacent tiers. Only metro counties have sustained meaningfully positive net births. Even there, the contribution has declined from a 2007 peak of 11,492 annually to roughly 4,400 in 2025, a 60.2% decline over this period.

Finally, net international migration has grown across every tier and in recent years has become the dominant or sole positive contributor to population change in much of nonmetro Iowa, especially since 2020. In rural counties, the post-2020 bars in figure 7 show international migration carrying nearly the entire positive load, with net births and net domestic migration contributing little, or in some years subtracting from it. The compositional shift is best seen in figure 8, which restates the same data as a share of each year's positive components. The chart isolates the question: “What fraction of growth came from each source, holding aside negative contributors?”

Figure 8. 

Source: U.S. Census Bureau

The shift is starkest in the nonmetro tiers. In every year since 2022, net international migration has been the sole positive contributor to population change in nonmetro Iowa—without it, every nonmetro tier would have lost population outright. In the nonmetro-adjacent panel, the net-births share fell from a 2010 peak of 77% to 0% by 2025, while the international-migration share rose from 23% to 100%. The nonmetro-not-adjacent tier shows the same pattern. Net-births share fell from 72% in 2010 to 0% in recent years, with international migration accounting for 100% of positive growth in the latest available years. Rural counties show the most extreme version, with international migration being the only positive component in 20 of the 25 years observed.

Even Iowa's metro counties—where net births remain a meaningful contributor—have grown more reliant on international migration. The international-migration share of metro positive components rose from 12% in 2010 to 40% in 2024, while the net-births share fell from 64% to 44% over the same period. Net domestic migration has contributed positively to metro-county growth in all but one year since 2005, though its share has fluctuated widely, ranging from single digits in some years to more than a third of positive components in others. Positive net births helped control the descent of Iowa’s nonmetro population between 2001 and roughly 2015. That cushion has now eroded across all four tiers and has effectively disappeared in the nonmetro tiers. International migration now carries any positive population change occurring outside Iowa's metropolitan cores. This dependence raises questions about the durability of recent population gains. International migration flows respond to federal policy choices, suggesting any meaningful change could remove the only positive contributor currently sustaining nonmetro Iowa's population.

Domestic migration continues to subtract from population growth across most of Iowa's counties, yet it is the component those counties can most directly influence—through housing supply, labor market opportunity, and cost of living. However, the county-level figures above blend two distinct flows that the Census Bureau's estimates cannot separate: Iowans relocating across county lines within the state and Iowans leaving Iowa for other states, along with the corresponding inflows. The following subsection uses American Community Survey (ACS) microdata to isolate the second of these flows—interstate movement—and characterize it in detail.

Metro and Nonmetro Interstate Migrants Follow Different Demographic and Socioeconomic Patterns

Every section to this point has counted residents and treated each as interchangeable—one body moving in offsets one body moving out. That framing answers how many residents Iowa's counties gain and lose but not whether the residents they gain resemble the ones they lose. A county can win its migration exchange by headcount and still lose ground if the people arriving carry less education, lower earnings, and weaker attachment to the labor force than the people departing. This section shifts the question from how many are moving to who is moving.

The previous subsection isolated net domestic migration as the component Iowa shapes most directly. Domestic migration responds most to the factors state and local policymakers and businesses can influence: housing supply, labor market opportunity, and cost of living. This subsection narrows the broader domestic-migration measure to interstate movers only, setting aside county-to-county moves within Iowa, and compares the people entering Iowa against those leaving. American Community Survey microdata samples for single-year, county-tier-specific flows are too small to support reliable point estimates of mover counts. However, the same samples are well-suited to characterizing the composition of those flows, since demographic shares are more stable than raw totals at this level of disaggregation. The comparison draws on pooled ACS data for the 2015–2024 period; additional detail appears in the "Methodology" section below.

Figure 9 focuses on metropolitan Iowa, defined as RUCC tier 1–3 counties. Figure 10 focuses on nonmetro Iowa, combining adjacent & non-adjacent nonmetro counties and rural counties (RUCC tier 4–9). Each figure presents the same demographic indicators side-by-side for in-migrants and out-migrants with the gap between the two shown as a third bar in percentage points. Positive values indicate the trait is more prevalent among in-migrants.

Figure 9. 

Source: IPUMS USA ACS 2015-2024, CSI Analysis

The people leaving metro Iowa for another state are more likely to be married, hold a bachelor's degree, and be employed than the people replacing them, while the people arriving are more likely to live in or near poverty. The largest single gap is marital status—37.9% of out-migrants are married, compared to just 27% of in-migrants. In-migrants concentrate more heavily in the 18–34 bracket (54.3% versus 49.7%), so metro Iowa's inflow also skews toward early-career adults still building careers and households, while its outflow skews toward established households taking their education and incomes with them.

The economic profiles diverge as well; 16.5% of in-migrants live below the poverty line and another 30.8% live near it, compared to 12.5% and 25.7% of out-migrants, respectively. Iowa's low cost of living likely explains part of this pattern. Common Sense Institute's March 2026 report, "The Inflation Hangover: How the Post-Pandemic Price Surge Reshaped Affordability in America," ranked Iowa the most affordable state in the nation in 2025.[5] The report found that a household earning the state's median wage retained 34.7% of its gross monthly income after covering necessities, the highest residual share of any state. Housing drives much of that advantage. CSI's quarterly housing affordability report found that as of March 2026, the average Iowan needed to work 38 hours per month to afford the mortgage payment on a typical single-family home—14 hours less than the national average.[6] Relative to wages, owning a home in Iowa is as affordable today as it was 25 years ago.[7] For households with modest incomes, that affordability advantage makes metro Iowa an attractive destination in a way that high-cost states cannot match. The result is an exchange in which metro Iowa draws residents seeking a lower cost of living while losing established, higher-earning households to other states.

That composition matters for the state's economic outlook. Measured by headcount, metro Iowa wins its interstate migration exchange. Measured by economic profile, the trade is less favorable because the average departing household takes more education and earning power out of Iowa than the average arriving household brings in. But this exchange is not necessarily a loss. Early-career adults are precisely the population a state with declining net births needs—but the return on that inflow depends on retention. If metro Iowa keeps these young arrivals as they advance careers and form families, today's more economically vulnerable in-migrants become tomorrow's established households. If it does not, the exchange amounts to trading peak-earning residents for entry-level replacements.

Figure 10.

Source: IPUMS USA ACS 2015-2024, CSI Analysis

Nonmetro Iowa's migration profile inverts the metro pattern. Where metro Iowa gains a more economically vulnerable population than it loses, nonmetro Iowa gains a more established one. In-migrants are less likely than out-migrants to live in or near poverty. In nonmetro Iowa, 30.4% of in-migrants fall below 200% of the federal poverty line, compared to 35.5% of out-migrants. Additionally, nonmetro Iowa has narrower gaps than metro Iowa between college educated and employed in- and out-migrants. The most distinctive difference, however, is age. Nonmetro in-migrants are notably more concentrated in the 35–64 bracket (28.9% versus 23.3%), pointing to an inflow of mid-career adults and families rather than recent graduates. In-migrants are also more likely to be Hispanic.

The people who move to nonmetro Iowa are more financially stable and further along in life than the people who leave. The makeup of nonmetro Iowa's inflow, therefore, is not what limits its population growth. Rather, the number of arrivals is its weakness. Too few people move in to offset those moving out, and as the prior subsection showed, no nonmetro tier has recorded a year of positive net domestic migration over the past quarter century. Put simply, nonmetro Iowa draws financially stable, mid-career households, but too few of them to grow. Metro Iowa, on the other hand, draws young workers and depends on retaining them, but that inflow skews young, unmarried, and economically vulnerable. Nearly half (47.3%) of metro in-migrants live in or near poverty, compared to 38.2% of out-migrants. In contrast, the outflow carries away married, college-educated, and employed households on net.

By the numbers, metro Iowa grows every year and nonmetro Iowa shrinks in nearly all of them. By the makeup of who moves, the two Iowas run structurally opposite exchanges. Metro Iowa trades established, higher-earning households for younger, lower-earning arrivals. Nonmetro Iowa attracts a low-volume, stable demographic, netting a population loss nearly every year.

Bottom Line

Iowa is growing, but most of its counties are not. Only 42 of the state’s 99 counties added residents in 2025, and the gains are clustered in and around its metropolitan areas. This marks the latest installment of a quarter-century pattern in which metro Iowa has grown every year while the state’s nonmetro tiers have shrunk nearly every year. The demographic engines behind that divide have also shifted. Natural increase, once the most reliable source of growth across the state, has eroded everywhere and effectively disappeared outside Iowa’s metro areas. Domestic migration has drained residents from nonmetro Iowa nearly every year. What remains is international migration, which now accounts for essentially all the positive population change occurring outside Iowa’s metropolitan areas.

Iowa’s dependence on international migration for demographic growth carries risk. International migration responds to federal immigration policy and to employer demand for foreign-born labor—forces over which Iowa communities have limited control. The 2025 estimates already show inflows cooling across the urban-rural divide. If policymakers want nonmetro Iowa's population to stabilize, the levers run through the three components of population change themselves. They can pursue policies aimed at raising natural increase—supporting young families through childcare, housing, and the cost of raising children. Fertility, however, responds to forces well beyond any single policy. Even if fertility increased tomorrow, it would take decades for a rise in births to begin shifting demographic trends among the working-age population. Policymakers can also make rural counties more competitive for domestic movers—the component a state shapes most directly—by addressing housing supply, labor market opportunity, and cost of living. Alternatively, they can continue to rely on the international inflows now carrying nonmetro growth. This approach proves the most immediately responsive of the three legs of the state demographic stool, but it also risks the most exposure to federal policy.

Future CSI research will continue to track these county-level trends as new Census Bureau estimates are released and as the composition of Iowa’s migration flows evolves.

Methodology

This analysis characterizes the demographic profile of migrants entering and leaving Iowa using microdata from the U.S. Census Bureau's American Community Survey (ACS), accessed through IPUMS USA at the University of Minnesota.[8] The ACS asks respondents to report their state, county, and Public Use Microdata Area (PUMA) of residence one year prior to the survey, allowing CSI to identify person-level migration flows and link migrants to demographic characteristics observed at the time of the survey. The analysis in this report pools nine ACS one-year samples covering survey years 2015 through 2024, excluding 2020.

Common Sense Institute restricted the sample to respondents whose IPUMS-coded migration status (MIGRATE1) indicates a move within the prior year, either across counties within a state or across state lines. The analysis then partitioned the sample into two non-overlapping populations: Iowa-leavers, defined as respondents whose prior-year state was Iowa but whose current state was not, and Iowa-enterers, defined as respondents currently residing in Iowa whose prior-year state was elsewhere in the United States.

To classify the rurality of each origin and destination, CSI assigned a Rural-Urban Continuum Code (RUCC) to every county in the United States using the U.S. Department of Agriculture Economic Research Service's 2023 Rural-Urban Continuum Codes (RUCC) vintage.[9] The analysis then collapsed the nine-level RUCC scheme into three tiers based on the metro/nonmetro and adjacency distinctions encoded in the RUCC framework itself: "Metro" (RUCC 1–3), "Adjacent nonmetro" (RUCC 4, 6, 8—nonmetro counties bordering a metro area), and "Non-adjacent nonmetro" (RUCC 5, 7, 9—nonmetro counties not bordering a metro area). Iowa contains no RUCC 1 counties; its largest metro, Des Moines, falls below the one-million population threshold required for that designation.

Linking each migrant to a county-level RUCC tier required a geographic crosswalk to identify the true county-of-residence. The IPUMS variable COUNTYFIP was available only for the most populous counties—Polk, Linn, Scott, Black Hawk, Johnson, and Woodbury. The remaining 93 Iowa counties are bundled into multi-county PUMAs designed to contain populations of roughly 100,000 each. CSI therefore assigned origin and destination tiers at the PUMA level rather than the county level. The destination tier was derived from the respondent's current PUMA (PUMA). The origin tier was derived from the prior-year migration PUMA (MIGPUMA1).

To translate PUMAs into RUCC tiers, CSI built a population-weighted modal-RUCC crosswalk. For each PUMA, CSI identified its constituent counties using the Census Bureau's tract-to-PUMA relationship files, joined those counties to their 2020 populations and 2023 RUCC codes, and assigned the PUMA to the tier whose constituent counties held the largest share of the PUMA's total population.[10] An equivalent population-weighted aggregation produced the MIGPUMA tier crosswalk used to classify migrant origins. Both crosswalks were built separately for the 2010 and 2020 PUMA boundary vintages, since IPUMS uses 2010-vintage PUMA codes for ACS samples through 2021 and 2020-vintage PUMA codes from 2022 onward. The analysis applied the appropriate vintage to each respondent based on the survey year of the underlying ACS sample.

After classification, CSI grouped the resulting flows into four headline categories defined by the cross-tabulation of origin tier and destination tier within each direction:

• Leavers: Metro Iowa to Elsewhere
• Leavers: Nonmetro Iowa to Elsewhere
• Enterers: Elsewhere to Metro Iowa
• Enterers: Elsewhere to Nonmetro Iowa

All summary statistics were computed using ACS person weights (PERWT) to produce population-representative estimates. Annualized flow volumes were obtained by dividing the pooled weighted total by the number of pooled survey years (nine). Demographic indicators—age structure, sex, race and ethnicity, educational attainment, marital status, presence of own children, employment status, citizenship status, poverty status, household income, and homeownership—were computed as weighted shares or weighted medians within each flow category. Educational attainment was restricted to respondents age 25 and older; employment status to respondents age 16 and older; and marital status to respondents age 18 and older.

Appendix

Figure 11. 

Source: U.S. Census Bureau

Figure 12. 

Source: U.S. Census Bureau

Figure 13. 

Source: U.S. Census Bureau

Figure 14. 

Note: The gray line indicates the five-year average.
Source: U.S. Census Bureau, U.S. Department of Agriculture

Figure 15. 

Source: U.S. Census Bureau

Table 1.

Source: U.S. Census Bureau, U.S. Department of Agriculture

Figure 16. 

Note: The gray line indicates the five-year average.
Source: U.S. Census Bureau, U.S. Department of Agriculture

Figure 17. 

Source: U.S. Census Bureau

Table 2.

Source: U.S. Census Bureau, U.S. Department of Agriculture

Figure 18. 

Note: The gray line indicates the five-year average.
Source: U.S. Census Bureau, U.S. Department of Agriculture

Figure 19. 

Source: U.S. Census Bureau

Table 3.

Net International Migration

Source: U.S. Census Bureau

Endnotes