Northern Virginia Regional Commission's One Region immigration study, Coronavirus (COVID-19) immigration study, and dashboard assessing the economic impact of immigrants in Northern Virginia. The report and a dashboard of key demographic and economic findings from the report are found here. Immigration Study Reports, maps, and charts are best viewed on a desktop or tablet. The Northern Virginia Regional Commission was pleased to collaborate with the Partnership for a New American Economy (NAE) and the Community Foundation for Northern Virginia on the study, One Region: Welcoming New Americans to Northern Virginia. The original study was published on March 12, 2020. It is a study of the economic impact of immigrants to the region. An addendum to the study was published on October 21, 2020 that provides immigrant data relevant to the COVID-19 pandemic crisis response . The research was conducted by NAE. NAE has undertaken similar studies throughout the United States. This One Region report dashboard summarizes and reports on immigration in the Northern Virginia region. This dashboard provides quick access to key data pieces found in the report. This One Region immigration dashboard provides data not only of the overall Northern Virginia region, but also on the localities within the region . A webinar was hosted on October 21, 2020. For copies of the presentations and video recording go to the webinar webpage. Download a copy of the original report, published March 2020 Overview of the One Region Report The One Region report is a comprehensive picture of new Americans in Northern Virginia (NOVA). It highlights the size and rapid growth in the immigrant population in the region and their impact on the local economy, including injecting more money into local businesses, property markets, and municipal budgets as consumers, homebuyers, and taxpayers. Immigrants are major contributors to Northern Virginia's (NOVA) economy as highlighted in the report. The NOVA immigrant population is diverse. These people emigrate, seeking a better life for themselves and their families. “Immigrants are a vital part of the economic and social fabric of Northern Virginia. Their success is our success, and we must continue to be a welcoming community for all to ensure our long-term prosperity,” said P. David Tarter, Chairman of the Northern Virginia Regional Commission and Mayor of the City of Falls Church. Immigrants are an indispensable part of the local Northern Virginia economy at all levels, as workers, business owners, taxpayers and consumers. Trivia: What is the foreign born share of the population in NOVA? What is the foreign born share of the population in NOVA? Source: U.S Census Bureau, 2018 American Community Survey, 5-Year Estimates. 27.6% Immigrants widen and deepen the labor market with a vast array of skills and levels of expertise. They help businesses, farms, and factories fill workforce gaps at all levels of the labor market, allowing companies to meet market demands and expand their operations, which leads to more job creation. * Except where otherwise noted, the term “immigrant” and “foreign-born” are used interchangeably throughout the NOVA Region Dashboard and in the "One Region" report. COVID-19 Addendum One Region Report Addendum on COVID-19 Response This brief provides a glimpse at the role of immigrants in Northern Virginia during the Covid-19 pandemic as well as the impact that the pandemic has had on the immigrant community. The immigrant population is especially vulnerable to gaps in our social safety nets. Understanding this population in Northern Virginia helps better inform local leaders as they aim to implement inclusive emergency response policies. The immigrant population is essential to our country’s rapid COVID-19 response efforts. Download a copy of the COVID-19 addendum report published October 2020 Data Charts and Key Findings by Report Topic (best viewed on desktop) The data is sourced from the U.S. Census Bureau American Community Survey (ACS) five-year estimates, as well as other sources. The ACS is a survey based on a sample of the population. Sample surveys include a degree of uncertainty and error in the data. The larger the population and housing units of an area or data variable, the more reliable the ACS data. The Northern Virginia regional data is more reliable than the county level data that is presented in the data charts. Users should interpret the data by keeping this in mind. Citizenship Entrepreneurship Internet Access Economy Healthcare Language Spoken Education Housing Labor Force Additional Immigrant Information (best viewed on desktop) Further information about Northern Virginia's immigrant population, from research NVRC has conducted separately from the One Region report, can be found on the People dashboard. People There is a myriad of non-governmental organizations (NGOs) that provide services to immigrants. A number of the local governments in Northern Virginia also provide links to information and services. Where to Get Help

Northern Virginia income, economically disadvantage populations, workforce, and more demographics, data and graphs by region and county. Analyzed by the Northern Virginia Regional Commission (NVRC). Economics Information on economics of the overall Northern Virginia region and its county and cities. Overall Information on economics of Northern Virginia incorporated towns . Towns

Immigrant entrepreneurship data compiled by the Northern Virginia Regional Commission's as part of the One Region immigration study, Coronavirus (COVID-19) immigration study, and data dashboard to assess the economic impact of immigrants in Northern Virginia. Entrepreneurship - Overall Reports, maps, and charts are best viewed on a desktop or tablet. Key Facts Entrepreneurship - Overall Immigrants are job creators In Northern Virginia, immigrant entrepreneurs – those who work for their own businesses, incorporated or not – are making their mark locally. 2013 to 2017 Period Key Facts: 47,837 total estimated immigrant entrepreneurs 42.5 percent of all entrepreneurs in the region are immigrants.

Northern Virginia town economically disadvantaged populations, poverty, free and reduced price school meal (FARM) student and more demographics, data and graphs. Analyzed by the Northern Virginia Regional Commission (NVRC). Economically Disadvantaged Overall Reports, maps, and charts are best viewed on a desktop or tablet. Economically Disadvantaged of Northern Virginia While Northern Virginia is known for having communities with some of the highest median incomes in the United States, we must recognize that there are segments of the community in need of assistance that live in one of the most prosperous regions in the country. Poverty The Northern Virginia region has some of the highest household incomes in the United States. However, there are persons in poverty in the region, and their needs must be recognized and addressed. The poverty rates of all counties and cities in Northern Virginia are shown in the following graphs. The poverty rate is the ratio of the number of persons in poverty divided by the number of persons for whom poverty status was determined. Not everyone had their poverty status determined so this figure will be less than the total population. About the Data and Proper Data Interpretation Poverty data is sourced from the U.S. Census Bureau 2000 Census and the American Community Survey (ACS). It is important to note that any data sourced from the ACS is based on a small sample of the population of a place. Areas with smaller populations, such as the cities of Northern Virginia, may have a larger margin of error in the data due to the survey sample size being small. This is less of an issue the larger the population. The margin of error is shown in the popup that is displayed when hovering over a bar in the bar charts. If there is a large increase or decrease in the estimate from one time period to the next, and the margin of error is large and overlaps other periods, then the large change between time periods is likely due to statistical sampling error and is not considered statistically significant. In addition to the margin of error, the accuracy of the American Community Survey data for an area can be gaged by evaluating the trend. If the data has a clear trend then the data from one period to the next can be deemed reliable Poverty Rate - Current Five-Year Estimates Northern Virginia's poverty rate is 6.0%, compared to 9.9% for Virginia and 12.5% for the nation according to the U.S. Census Bureau American Community Survey. All jurisdictions in the United States are included in the five-year American Community Survey estimates. Out of all 3,144 jurisdictions in the USA, two of the fifteen lowest poverty rates are located in the Northern Virginia localities of Falls Church (8th) and Loudoun County (12th). Loudoun County and Falls Church are also the 1stt and 11th ranked for median household income, respectively. However, there are persons in poverty in Loudoun, Falls Church, and the rest of the region, and their needs must be recognized and addressed. Poverty Rate - Current One-Year Estimates Those jurisdictions with a population of 65,000 or more are included in the one-year American Community Survey estimates. The poverty rates for the five largest jurisdictions in Northern Virginia are shown in this graph. The Northern Virginia regional poverty rate was 6.1% in 2024, which is nearly half the poverty rate of the nation. Out of the 850 jurisdictions with a population of 65,000 or more in the USA, one of the twenty lowest poverty rates is located in the Northern Virginia locality of Loudoun County (20th). Loudoun County is also the number one ranked for median household income. However, there are persons in poverty in Loudoun and the rest of the region and their needs must be recognized. Poverty Rate - Historic Compared to Current Five-Year Estimates Northern Virginia's poverty rate has experienced a similar pattern to the Commonwealth of Virginia and the United States over time. From 1999 to the 2010-2014 period there was an increase in the percent of persons in poverty. The rate in poverty has gradually lessened since the 2010-2014 period, reaching 6.0% in the 2020-2024 period. Poverty Rate - Historic Compared to Current One-Year Estimates The poverty rate patterns over time, for the regions large jurisdictions (population of 65,000 or more), are shown in the following graph. The Northern Virginia regional poverty rate, for the one-year estimates, represents the five largest jurisdictions in Northern Virginia only. The persons in poverty data has large year-to-year fluctuations due to the small sample size of the survey, together with the small amount of persons in poverty. The margins of error (displayed in the graph pop-ups), are large for the poverty one-years estimates, making any poverty trends undiscernible. However, the low to high ranges of poverty over time for each jurisdiction and the region, and comparisons between jurisdictions and the region can be gleaned. For instance, Northern Virginia's poverty rate has ranged from approximately 6% to 7% between 2010 and 2024, and Loudoun County’s poverty rate has been consistently lower than the other large jurisdictions. Given the unreliability of single-year poverty estimates, utilization of five-year estimates are strongly recommended for all Northern Virginia jurisdictions and the region when analyzing trends, planning, and developing policies. The American Community Survey 5-year estimates have a significantly larger sample size.

Northern Virginia population growth, minority-majority transition, foreign born population transformation, and more demographics, data and graphs by region and county. Analyzed by the Northern Virginia Regional Commission (NVRC). People / Population Information on the people of the overall Northern Virginia region and it's county and cities. Overall Information on the people of Northern Virginia's incorporated towns . Towns

Federal impact reports and studies on Northern Virginia, DC Metro Area, and Virginia. Federal Monitoring Reports/Resources NVRC Presentations School Planners Forum - June 4, 2025 Federal Impact on School Enrollment Presentation - NVRC's Senior Regional Demographer, Jill Kaneff, presented at the annual regional school planners forum hosted by Loudoun County Public Schools. The forum brought together school planners from across the D.C. region and beyond. Guidance on key demographic and economic indicators to monitor was provided to assist schools plan for the federal impacts on enrollment during these uncertain times caused by the federal layoffs and cutbacks. Virginia House Emergency Committee on the Impacts of Federal Workforce and Funding Reductions, April 8, 2025 NVRC's Senior Regional Demographer, Jill Kaneff, and the NVRC Chair presented at the committee meeting. The Northern Virginia Federal Workforce presentation is an overview of Northern Virginia federal workforce and data resources available for policy makers and the general public. Economy Virginia Economic Impacts The University of Virginia's Weldon Cooper Center for Public Service produces a quarterly economic forecast for the Commonwealth of Virginia. The center also publishes special studies and presentations that focus on the federal impacts. View the Weldon Cooper Center's research reports. Washington D.C. Metropolitan Area Economic Impacts The Metropolitan Washington Council of Governments (MWCOG) partners with the Brookings Metro program of the Brookings Institute to produce the DMV Monitor, an interactive dashboard designed to track a wide range of economic indicators, including job growth, real estate, venture capital, and tourism, and provide in-depth analysis of the region’s economic, social, and fiscal health. View the DMV Monitor . Housing Market Bright MLS Bright MLS tracks and reports on the housing market conditions of Northern Virginia's and the Greater D.C. metropolitan area. Bright MLS News and Insights offers insightful research and surveys, covering topics such as the effects of DOGE and federal spending cuts. Featured informative resources also include the following. Monthly Market Report The monthly market reports include a Washington D.C. metro area market report and individual Northern Virginia jurisdiction market reports . These reports present market trends and comparative graphs showing current and historical data. Special Presentation in Coordination with NVRC Lisa Sturtevant, PhD, Chief Economist with Bright MLS, presented at the Loudoun County Public Schools Planners and GIS Forum on June 4, 2025: D.C. Metropolitan Area Housing Market Trends and Outlook . This presentation includes insightful comparative market trends not found in the monthly market reports. The forum brought together school planners from across the D.C. region and beyond. This presentation was part of a two set series on the federal impacts, with the first presentation being NVRC's presentation on Federal Impact on School Enrollment . Northern Virginia Association of Realtors The Northern Virginia Association of Realtor tracks and reports on the housing market conditions of the inner jurisdictions of Northern Virginia with data provided by George Mason University's Center for Regional Analysis and Bright MLS. On an annual basis, a report on housing market forecasts is produced in conjunction with the Center for Regional Analysis at George Mason University (GMU-CRA). DMV Monitor The Metropolitan Washington Council of Governments (MWCOG) partners with the Brookings Metro program of the Brookings Institute to produce the DMV Monitor, an interactive dashboard designed to track a wide range of economic indicators, including job growth, real estate, venture capital, and tourism, and provide in-depth analysis of the region’s economic, social, and fiscal health. View the DMV Monitor .

Northern Virginia income, economically disadvantage populations, workforce, and more demographics, data and graphs by region and county. Analyzed by the Northern Virginia Regional Commission (NVRC). Household Income Distribution Overall Reports, maps, and charts are best viewed on a desktop or tablet. Household Income Distribution of Northern Virginia Northern Virginia is known for having communities with some of the highest incomes in the United States, including the county with the highest median household income in the nation. High incomes coincide with the large, thriving business community of the Northern Virginia region. While high incomes exist, we must recognize that there are segments of the community that are lower income and in need of assistance that live in this prosperous region of the country. About the Data and Proper Data Interpretation Median household income data is sourced from the U.S. Census Bureau 2000 Census and the American Community Survey (ACS). It is important to note that any data sourced from the ACS is based on a small sample of the population of a place. Areas with smaller populations, such as the cities of Northern Virginia, may have a larger margin of error in the data due to the survey sample size being small. This is less of an issue the larger the population. The margin of error is shown in the popup that is displayed when hovering over a bar in the bar charts. If there is a large increase or decrease in the estimate from one time period to the next, and the margin of error is large and overlaps other periods, then the large change between time periods is likely due to statistical sampling error and is not considered statistically significant. In addition to the margin of error, the accuracy of the American Community Survey data for an area can be gaged by evaluating the trend. If the data has a clear trend then the data from one period to the next can be deemed reliable. Five-Year Estimates - Current All jurisdictions in the United States are included in the five-year American Community Survey estimates. The share of households in each income cohort for all jurisdictions in Northern Virginia are shown in this graph. While Northern Virginia is known for having communities with some of the highest median incomes in the United States, it must be recognized that there are segments of the community in need of assistance that live in one of the most prosperous regions in the country. It also must be recognized that the region's high cost of housing can be burdensome for both the low and moderate income households (earning up to $150,000), particularly first time home buyers , so there is a significant need for more affordable housing. For further information on the affordable housing needs for the middle-income, see the NVRC report Shifting Migration Patterns of Northern Virginia: Affordable Housing Needs published January 2025. One-Year Estimates - Current Those jurisdictions with a population of 65,000 or more are included in the one-year American Community Survey estimates, of which there are five Northern Virginia jurisdictions included. The share of households in each income cohort for the five largest jurisdictions in Northern Virginia are shown in this graph. The Northern Virginia regional household income distribution, for the one-year estimates, is representative of the five largest jurisdictions in Northern Virginia only. While Northern Virginia is known for having communities with some of the highest median incomes in the United States, it must be recognized that there are segments of the community in need of assistance that live in one of the most prosperous regions in the country. It also must be recognized that the region's high cost of housing can be burdensome for both the low and moderate income households (earning up to $150,000), particularly first time home buyers, so there is a significant need for more affordable housing. For further information on the affordable housing needs for the middle-income, see the NVRC report Shifting Migration Patterns of Northern Virginia: Affordable Housing Needs published January 2025.

Northern Virginia town economically disadvantaged populations, poverty, free and reduced price school meal (FARM) student and more demographics, data and graphs. Analyzed by the Northern Virginia Regional Commission (NVRC). Safety Net Participants Overall Reports, maps, and charts are best viewed on a desktop or tablet. Safety Net Participants While Northern Virginia is known for having communities with some of the highest median incomes in the United States, we must recognize that there are segments of the community in need of assistance that live in one of the most prosperous regions in the country. Affordable Care Act The Affordable Care Act (ACA) is the comprehensive health care reform law enacted in March 2010. More than 151,000 residents in Northern Virginia in 2024 received health insurance through the Affordable Care Act. Supplemental Nutrition Assistance Program The Supplemental Nutrition Assistance Program (SNAP) expenditures in Northern Virginia from 2011 to 2024 are shown in this graph, and the participants are shown in the tables below. Since 2011, the peak amount of expenditures was reached in 2022 due to the COVID-19 pandemic and its economic downturn. The COVID-19 pandemic hit the world and its impact on the Northern Virginia region was significant from a health and economic standpoint. The temporary boost to SNAP benefits put in place during the COVID-19 pandemic, known as emergency allotments, ended nationwide after the February 2023 issuance. Temporary Assistance for Needy Families Program The Temporary Assistance for Needy Families (TANF) and TANF-UP (TANF Unemployed-Families) expenditures in Northern Virginia from 2019 to 2024 are shown in this graph, and the participants are shown in the tables below. Since 2019, the peak amount of expenditures was reached in 2022 due to the COVID-19 pandemic and its economic downturn. The COVID-19 pandemic hit the world and its impact on the Northern Virginia region was significant from a health and economic standpoint. For additional information on the TANF and TANF-UP programs view the Virginia Department of Social Services's TANF program flyer . Medicaid Expansion The Medicaid Expansion Dashboard, which is maintained by the Virginia Department Medical Assistance Services , shows new health coverage for adults by overall enrollment, age, gender, family income, locality and region of residence.

Northern Virginia educational attainment, public school student enrollment, and more demographics, data and graphs by region and county. Analyzed by the Northern Virginia Regional Commission (NVRC). Student Enrollment Overall Reports, maps, and charts are best viewed on a desktop or tablet. Public School Student Enrollment of Northern Virginia Overview Northern Virginia experienced sustained public school enrollment growth from 2004 through 2019, increasing from 315,898 students to a peak of 423,670. Since 2019, enrollment has declined in four of the past six years, including the most recent school year. Student enrollment in 2025 totaled 405,457. Note, the annual enrollment figures reflect September 30th of each year. Key Highlights Declining Student to Total Population Share: Since 2019, both total enrollment and the student share of the population have fallen. The student share declined from 16.7% in 2019 to a low of 15.8% in 2024. The 2025 share is currently unavailable, but will be available in mid-2026 when population data for 2025 is released by the U.S. Census Bureau. Multiple Contributing Factors: Recent declines in public school enrollment reflect a combination of factors, including declining births and birth rates, an aging population, accelerated out-migration of families due to housing costs, and elevation participation in home-schooling and private education options post-COVID 19 pandemic. Generational Transition: Public school enrollment trends closely track regional birth patterns, typically with a five-year lag. Births and birth rates in Northern Virginia have declined steadily since 2007, resulting in progressively smaller elementary school enrollment since 2013. Larger pre-2013 cohorts that supported enrollment growth are graduating and being replaced by smaller student populations, making continued enrollment decline increasingly likely. Future Growth and Planning Northern Virginia is undergoing a generational transition in its student population. The larger student populations that entered school prior to 2013 and sustained growth through the 2010s are now graduating from the school system, while smaller student populations advance through each grade. Continued enrollment declines are increasingly likely over the next five to ten years. In the longer term, Northern Virginia is projected to have substantial population growth. The region's population exceeded 2.60 million in 2024 and is forecast to surpass 3 million by 2040, according to the NVRC Demographic and Economic Fact Sheet . However, aging of the population and declining birth rates are reducing the number of school-age children entering the public school system. In addition, higher housing costs and other economic pressures are contributing to slow in-migration of families and prompting families to move out of the region. These factors are expected to result in overall stagnation or declines in student enrollment for the region, but specific areas of the region with large amounts of residential development will have increased enrollment. In summary, a multitude of variables alter student enrollment trends, including new development, transfers to and from private schools, in- and out-migration rates, and size and composition of families in existing housing stock. With growth and demographic shifts comes challenges in maintaining the high quality of education and school facilities in the region. Ensuring the continued excellence of education necessitates strategic planning and the acquisition of land or facilities for future school development, which has become increasingly complex in the region due to the limited supply of available land.

Housing characteristics compiled by the Northern Virginia Regional Commission's as part of the One Region immigration study, coronavirus (COVID-19) immigration study, and data dashboard to assess the economic impact of immigrants in Northern Virginia. Housing Characteristics Reports, maps, and charts are best viewed on a desktop or tablet. Key Facts Housing Foreign born headed households, especially those on the lower end of the income spectrum have significantly larger household sizes than U.S. born headed households. COVID-19 More occupants per household present opportunities for transmission of COVID-19 among members within that household since COVID-19 is spread through close contact. Housing instability from the pandemic requires a very proactive role from local communities. 2014 to 2018 Five-Year Estimates Key Facts: Foreign born headed households, in general, are larger than U.S. Born headed households in Northern Virginia and its localities. Northern Virginia has a foreign born average household size of 3.22, while U.S. born headed is 2.39. The gap between the foreign born and U.S. born average household size in Northern Virginia shrinks with each higher income quintile, almost reaching parity at the top among the highest income households. The lowest income quintile has a gap of 0.9 persons per household, while the highest income quintile has a gap of 0.2 persons per household. The housing tenure of the foreign born in Northern Virginia is 58 percent owner and 42 percent renter. This distribution varies widely by locality. The innermost, urban localities of Arlington and Alexandria have a higher rate of renters than the outer, suburban localities. The housing type of the foreign born in Northern Virginia is 60.5 percent single-family, 37.5 percent multi-family, and 2.0 percent other. This distribution varies widely by locality. The innermost, urban localities of Alexandria and Arlington have a majority residing in multi-family and the outer, suburban localities have a majority residing in single-family. Explore housing topics by clicking on the tabs below

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Northern Virginia town population growth, minority-majority transition, foreign born population transformation, and more demographics, data and graphs. Analyzed by the Northern Virginia Regional Commission (NVRC). Foreign Born and Immigrants of Towns Reports, maps, and charts are best viewed on a desktop or tablet. Foreign Born and Immigrant Population of Towns Overview The Washington, D.C. metropolitan area is one of the most diverse in the country when taking into consideration the minority and foreign born (immigrant) population make-up. Northern Virginia contains a sizable amount of the metropolitan area's diverse population. The foreign born or immigrant population is transforming the region and many of it's towns. Note, the terms foreign born and immigrant are used interchangeably throughout the NOVA Region Dashboard. It is immigration that has been driving many of the major demographic trends in the region, including: School enrollment changes Sizable increases in the number of Hispanics and Asians Population and labor force growth About the Data and Proper Data Interpretation Foreign born population data is sourced from the U.S. Census Bureau 2000 Census and the American Community Survey. All of the incorporated towns in Northern Virginia have a population of less than 65,000 persons. One-year ACS estimates do not exist for incorporated places with a population of less than 65,000. All incorporated towns and places in the United States are included in the five-year ACS estimates. It is important to note that any data sourced from the ACS is based on a small sample of the population of a place. The ACS estimates for places with smaller populations such as Clifton, Dumfries, Hamilton, Haymarket, Hillsboro, Lovettsville, Middleburg, and Quantico can be unreliable if the margin of error is large. The margin of error is shown in the popup that is displayed when hovering over a bar in the bar charts. If there is a large increase or decrease in the estimate from one time period to the next, and the margin of error is large and overlaps other periods, then the large change between time periods is likely due to statistical sampling error and is not considered statistically significant. In addition to the margin of error, the accuracy of the American Community Survey data for an area can be gaged by evaluating the trend. If the data has a clear trend then the data from one period to the next can be deemed reliable. Foreign Born Population - Current Foreign Born Population Share - Current The region's highest ranked county/city is Manassas Park City, ranking 8th in the nation at 36.8%. Herndon boasts one of the largest foreign-born populations in the country, at 42.2%. Statistically, Herndon is not significantly different from Manassas Park due to the data's margins of error. Towns that are estimated to have lower foreign born population shares than the Commonwealth of Virginia are all located within rural Loudoun County (Lovettsville, Purcellville, Hamilton, Middleburg, Round Hill), except for Clifton which is located in rural Fairfax County. Note, the town of Hillsboro's 2020-2024 estimate of 29.1% foreign born is considered highly unreliable. This is evidenced by the large rise compared to previous five-year periods, as shown in the Historic Compared to Current chart in the next section. It is additionally reinforced by the wide margin of error of +/-37.6%, which stems from the town's small survey sample size. Foreign Born Population - Historic Compared to Current Foreign Born Population Share - Historic Compared to Current Immigration has been driving many of the major demographic trends in the region. The foreign born population is transforming the region. Northern Virginia's population was 21.4% foreign born in 2000 and has risen to 28.2% currently. The largest transformations since 2000 have occurred in the towns of Dumfries, Haymarket, Leesburg, Lovettsville, and Occoquan. All of these incorporated towns are located in the outer-core, which is where the majority of the region's growth has occurred. Note, the American Community Survey is a survey with a small sample size. Due to the small size of many Northern Virginia towns and small sample size of the survey, the median household income of towns should be used with caution and the margin of error of the median household income should be taken into consideration. If there is a large increase or decrease in the estimate from one time period to the next, and the margin of error is large and overlaps other periods, then the large change between time periods is likely due to statistical sampling error and the data should be used with caution. The margin of error is shown in the popup that is displayed when hovering over a bar in the bar charts. In addition to the margin of error, the accuracy of the American Community Survey data for an area can be gaged by evaluating the trend. If the data does not have a clear trend, and the margin of error is large and overlaps other periods, then the large change between time periods is likely due to statistical sampling error and the data should be used with caution.