Population & age
- Total population
- 22,021
- Median age
- 45.4
Kershaw County · Columbia, SC · Population 22,021
Camden, SC (ZIP 29020) sits in Kershaw County within the Columbia metro area. The page draws on 2 federal data feeds retrieved Apr 27. Top health signal: High Blood Pressure comes in above the national average at 43.8%. NCES lists 8 schools serving the area, 8 non-charter. 4 colleges and universities serve the area, with median in-state tuition of $9,473. IRS data shows average household income (AGI) of $68,102, well above the ~$45K national average per return. BLS QCEW reports average annual pay of $49,084 per worker, roughly 25% below the US average. FEMA has issued 28 federal disaster declarations affecting this ZIP since 1977 — a high-frequency exposure profile. County Health Rankings reports 12,077 years of potential life lost per 100,000 (2025) — well above the national county median. 33.5% of residents in this county are flagged low-access by USDA's 2025 Food Environment Atlas — a notable supermarket-access gap. South Carolina levies a graduated state income tax (top rate 6.20%); a household at the local median AGI of $68,102 would pay roughly $2,533/year before deductions. IRS migration data (2022-2023) shows a net gain of 2,167 residents (857 households) — the ZIP's primary county is growing. Healthcare access and school options both run strong here, giving residents a wide menu of providers and enrollment choices nearby. Notable: median household income $55,972, fair market rent of $970 for a two-bedroom, and a typical home value of $235,984, up 0.6% over the past year. Every figure on this page links to its underlying federal dataset with a retrieval date so you can audit the freshness yourself.
Studio
$810
/month
1 Bed
$810
/month
2 Bed
$970
/month
3 Bed
$1,170
/month
4 Bed
$1,400
/month
HUD Fair Market Rents represent the 40th percentile of standard-quality rental housing in this area. FY2026 data.
$235,984
Zillow Home Value Index (ZHVI) · as of March 2026
+0.6%
vs. March 2025
+29.9%
vs. March 2021
Columbia, SC
Metropolitan statistical area
Source: Zillow Research, ZHVI All Homes (SFR, Condo/Co-op) Time Series (zillow.com/research/data). Zillow Home Value Index (ZHVI) is copyrighted by Zillow, Inc.
New housing units permitted
492
Across 425 permitted buildings. Total construction value: $114.8M.
Single-family
386
78% of total units
Multifamily (2+ unit)
106
22% of total units
Single-family value
$99.9M
construction value
Multifamily value
$14.9M
construction value
Aggregated from 2 counties touching this ZIP (2024).
Source: U.S. Census Bureau Building Permits Survey (census.gov/construction/bps). Public domain. BPS reports annual residential building permits from local permit-issuing jurisdictions, aggregated to county. A permit reflects intent to build, not a completed unit — actual construction lags by 6-24 months for multifamily projects.
Tax returns filed
10,940
Average AGI
$68,102
Avg property tax
$144
EITC participation
21.0%
Income distribution
Avg mortgage interest
$374
Avg charitable contribution
$723
Avg capital gains
$4,064
Avg total income tax
—
Source: IRS Statistics of Income — Individual Income Tax Statistics by ZIP Code (irs.gov). Public domain. Dollar columns reported in thousands by the IRS; figures here display real dollars. Total ZCTA AGI for the area was $745.0M across all reported brackets.
Business establishments
587
Total employment
7,171
Annual payroll
$264.7M
Average annual pay
$36,908
Source: U.S. Census Bureau, ZIP Business Patterns (census.gov). Public domain. ZBP covers establishments with paid employees; Census suppresses employment and payroll values when fewer employers operate in a ZIP than would protect their confidentiality.
Average annual pay
$49,084
Average weekly wage
$944
Total employment
18,335
Total establishments
1,568
That is roughly 25% below the US national average of $65,470 per worker.
Source: U.S. Bureau of Labor Statistics, Quarterly Census of Employment and Wages (bls.gov/cew). Public domain. QCEW is derived from state unemployment-insurance filings and covers ~95% of US jobs. Figures are county-level totals assigned to ZIPs whose primary county matches; small-employer cells are suppressed by BLS to protect employer confidentiality.
Unemployment rate
4.1%
That tracks the US national unemployment rate of about 4.0%.
Labor force
32,199
Employed
30,890
Unemployed
1,309
Based on Kershaw County, SC data (2024).
Source: U.S. Bureau of Labor Statistics, Local Area Unemployment Statistics (bls.gov/lau). Public domain. LAUS publishes monthly and annual labor-force estimates for every US county. Figures are county-level totals assigned to ZIPs whose primary county matches.
FDIC-insured bank branches
9
Typical banking access
A standard suburban / mid-density branch count for this area.
Total deposits
$795.2M
across all branches in this ZIP
Distinct institutions
8
different banks operating here
Top banks by deposits in this ZIP
Based on FDIC-insured branch offices as of June 30, 2024.
Source: FDIC Summary of Deposits (fdic.gov). Annual June-30 snapshot of every FDIC-insured branch and the deposits booked there. Figures cover all institutions reporting a branch address in this ZIP.
Federally funded health-center sites
2
Multiple health-center sites
A handful of federally funded community health centers serve residents — typical of mid-density suburban and small-urban areas.
FQHC sites
2
federally qualified
Look-Alike sites
0
FQHC equivalents
Avg hours / week
37.5
across sites in this ZIP
Sites in this ZIP
Federally Qualified Health Centers (FQHCs) and Look-Alike sites provide primary care on a sliding-fee scale, regardless of ability to pay. Active sites only; data refreshed 2026.
Source: HRSA Bureau of Primary Health Care (data.hrsa.gov). Per-ZIP counts of active service-delivery sites operated by Health Center Program grantees and Look-Alike organizations.
Facilities located inside ZIP 29020 from CMS Provider Data. Star ratings reflect Overall Hospital Quality where applicable; “Not rated” means the facility didn't report enough measures to qualify.
Hospitals (1)
KERSHAWHEALTH
1315 ROBERTS STREET, CAMDEN, SC, 29020
Source: Centers for Medicare & Medicaid Services Provider Data (data.cms.gov). Public domain.
FTA tracks transit service at the urbanized-area level. Numbers below reflect the agencies and modes serving the area that contains this ZIP, not stop-level coverage.
Service status
Available
Columbia, SC
Reporting agencies
1
Largest: Central Midlands Regional Transportation Authority
Annual ridership
—
unlinked trips · 2024
Source: U.S. Federal Transit Administration, National Transit Database (transit.dot.gov). Public domain.
Public EV charging stations
3
Established EV charging
Multiple public charging stations across the ZIP — typical of mid-density suburban and small-urban areas with active EV adoption.
Level 2 ports
8
AC charging — workplace, retail, home
DC Fast ports
0
Highway-class fast charging
Charging networks
Active public stations only. Snapshot taken 2026; AFDC's underlying registry refreshes continuously as stations open and close.
Source: U.S. Department of Energy via NREL (afdc.energy.gov). Per-ZIP counts of active public alternative-fuel stations (electric, hydrogen, propane, CNG, biodiesel, E85, LNG, renewable diesel) and EV charging-port totals.
Public-library outlets
2
Multiple library outlets
Several public-library outlets within the ZIP, giving residents real choice in branch hours, programming, and walk-in distance.
Buildings
1
1 central
Avg hours / week
27
across outlets in this ZIP
Avg square feet
13,660
per outlet
Outlets in this ZIP
Includes 1 bookmobile — service location varies; check the system's schedule.
Public libraries provide free WiFi, computer access, children's programming, job-seeking resources, and meeting space — community infrastructure beyond books. FY2023 outlet inventory from the federal Public Libraries Survey.
Source: Institute of Museum and Library Services (imls.gov). Per-ZIP counts of active public-library outlets — central buildings, branches, and bookmobiles — operated by federally reporting library systems.
Federally Declared Disasters
28
Date Range
1977–2026
Most Recent Declaration
SEVERE WINTER STORM
Winter Storm — declared January 23, 2026 (DR-3632)
Incident period: January 21, 2026 – January 27, 2026
Top Incident Types
Individual Assistance
4
Direct help to disaster survivors
Households Program
4
Housing & temporary lodging support
Public Assistance
26
Repair of public facilities & roads
Hazard Mitigation
9
Funding to reduce future disaster risk
FEMA declares disasters at the county level; counts here include every federally declared disaster touching any county that overlaps this ZIP. Statewide declarations and pre-1964 records without county granularity are excluded. Program flags reflect which FEMA assistance categories were activated (Individual Assistance, Households, Public Assistance, Hazard Mitigation). Source: fema.gov/openfema. Public domain.
30-year averages (1991-2020) from the nearest GHCN-D weather station. Temperature and precipitation values reflect typical annual conditions, not any single year.
Avg. temperature
62.9°F
50.6° – 75.2°
Annual precipitation
38.3"
Diurnal range
24.6°F
Day-night swing
Heating · cooling days
2,758.7 · 2,023.6
Annual base 65°F
Nearest station: WATEREE DAM, SC US, 7.5 miles from the centroid of Camden, SC (ZIP 29020)
Source: NOAA National Centers for Environmental Information, 1991–2020 U.S. Climate Normals (ncei.noaa.gov). Public domain.
Years of potential life lost (per 100K)
12,077
That is roughly 3,877 years per 100,000 above the national county median (~8,200).
Premature death is the headline composite outcome CHR reports — age-adjusted, all-cause, before age 75.
Fair or poor health
18%
of adults self-report
Poor physical health days
4.3
avg per adult per month
Poor mental health days
5.8
avg per adult per month
Uninsured
10.1%
of residents under 65
Primary care MDs
57
per 100,000 residents
Preventable hospital stays
2,140
per 100K Medicare enrollees
Food environment (0-10)
7.5
10 = best access & security
Exercise access
37%
residents near a facility
Flu vaccinated
50%
of Medicare enrollees
Low birth weight (under 2,500 g) accounts for 9.7% of live births in this county — an early-life health input that downstream outcomes track against.
Based on Kershaw data (2025 CHR release).
Source: County Health Rankings & Roadmaps, University of Wisconsin Population Health Institute (countyhealthrankings.org). Annual release. Underlying source datasets vary by measure (CDC BRFSS, NCHS Vital Statistics, AHA, USDA Food Environment Atlas, and others). Figures are county-level and assigned to every ZIP whose primary county matches.
Food access status
Significant food access concerns
33.5% of Kershaw County, SC residents live more than 1 mile (urban) or 10 miles (rural) from the nearest supermarket.
Grocery stores
0.15
per 1,000 residents
Supercenters & clubs
—
per 1,000 residents
SNAP-authorized stores
0.94
accepting food benefits
Fast-food restaurants
0.56
per 1,000 residents
Among low-income residents, 12.1% are low-access — those without a supermarket within 1 mile (urban) or 10 miles (rural).
Per-1,000 figures show how many of each store type exist in Kershaw County, SC for every 1,000 residents. Higher grocery and supercenter density usually means easier access to fresh food; higher convenience-store-only density (with low grocery rate) often signals a food swamp.
Source: USDA Economic Research Service, Food Environment Atlas (ers.usda.gov). County-level metrics fanned to ZIP via the primary county in the Census ZCTA-county relationship file. Variable years differ per family (stores ~2020, low-access ~2019).
FBI publishes crime data at the county level. Numbers below cover the primary county that contains this ZIP. Rates are per 100,000 residents in the area covered by reporting agencies.
Violent crime rate
—
per 100K residents · 124 reports
Property crime rate
—
per 100K residents · 295 reports
Homicide
4
Robbery
7
Burglary
51
Vehicle theft
44
County-level data for Lee (2024)
Source: U.S. Federal Bureau of Investigation, Uniform Crime Reporting Program (cde.ucr.cjis.gov). Public domain. Coverage varies by reporting agency; areas with partial agency coverage may understate true crime totals.
Net migration (2022-2023)
▲+2,167 people
+857 households • +$67.8M net AGI flow
Moved in
3,171households
6,658 people • $202.6M AGI
Moved out
2,314households
4,491 people • $134.8M AGI
Where new residents came from
Where departing residents went
Incoming households reported an average AGI of $63,906 versus departing households' $58,260.
Source: U.S. Internal Revenue Service, Statistics of Income, Migration Data (irs.gov). Public domain. Migration is measured by year-over-year changes in the address on individual tax returns; figures are county-level totals attributed to ZIPs whose primary county matches. Foreign migration contributes to inflow/outflow totals but does not appear in the top-county lists. Small flows are suppressed by IRS to protect taxpayer confidentiality.
State-level rules that apply to every resident of ZIP 29020. Numbers reflect the most recent published year per source.
Income tax
6.20%
graduated · 2 brackets
Sales tax (combined)
7.49%
State 6.00% · avg local 1.49%
Property tax (effective)
0.50%
Median $1,602/year
Tax burden rank
13 of 50
9.20% of personal income
For ZIP 29020: At this ZIP's median AGI of $68,102, the estimated state income tax (before deductions) runs about $2,533 per year. Applied to this ZIP's typical home value of $235,984, that works out to roughly $1,171/year in property tax.
Program
Voluntary (private insurance framework)
Voluntary (private insurance framework)
SNAP eligibility
130% FPL
Broad-Based Categorical Eligibility (raises gross income limit above federal 130% floor). No asset test.
Sources: Tax Foundation (state tax rates & brackets), Bipartisan Policy Center (paid family leave), USDA FNS (SNAP categorical eligibility).
Nearby ZIPs by distance
29032 (7.6 mi) · 29175 (9.1 mi) · 29078 (Lugoff, 11.6 mi) · 29009 (Bethune, 14.9 mi) · 29128 (Boykin, 15.3 mi) · 29045 (Columbia, 15.9 mi)
Compare ZIP-level stats — population, schools, housing, climate — across nearby areas. Source: U.S. Census Bureau ZCTA basemap.
All data on this page is sourced from federal government datasets · Not AI-generated · Methodology
Crude prevalence estimates from CDC PLACES, derived from BRFSS small-area modeling. Population-level figures only.
37.7%
4.7pp above the 33.0% national rate.
43.8%
11.8pp above the 32.0% national rate.
21.3%
Tracks close to the 22.0% national rate.
82.6%
6.6pp above the 76.0% national rate.
11.7%
Tracks close to the 13.0% national rate.
16.9%
5.9pp above the 11.0% national rate.
8 schools serve this ZIP, including 8 non-charter.
| School | Type | Grades | Enrollment |
|---|---|---|---|
| Camden High | Public | 9–12 | 1,012 |
| Camden Middle | Public | 6–8 | 850 |
| Jackson School | Public | -1–5 | 548 |
| Camden Elementary | Public | -1–5 | 532 |
| Pine Tree Hill Elementary | Public | -1–5 | 498 |
Showing top 5 by enrollment. 3 more schools serve this ZIP.
Schools listed from NCES Common Core of Data via the Urban Institute Education Data Portal.
Fresh.NCES CCD via Urban Institute EDP · Apr 27, 2026Colleges in this area
4
Median in-state tuition
$9,473
Median earnings (10 yr)
$25,351
Camden, SC · 29020
Denmark, SC · 29042
Denmark, SC · 29042
Elgin, SC · 29045
Source: U.S. Department of Education College Scorecard (collegescorecard.ed.gov). Public domain data. Earnings figures reflect median earnings 10 years after entry for federally-aided students.
Camden, SC (ZIP 29020) sits in Kershaw County within the Columbia metro area. The page draws on 2 federal data feeds retrieved Apr 27. Top health signal: High Blood Pressure comes in above the national average at 43.8%. NCES lists 8 schools serving the area, 8 non-charter. 4 colleges and universities serve the area, with median in-state tuition of $9,473. IRS data shows average household income (AGI) of $68,102, well above the ~$45K national average per return. BLS QCEW reports average annual pay of $49,084 per worker, roughly 25% below the US average. FEMA has issued 28 federal disaster declarations affecting this ZIP since 1977 — a high-frequency exposure profile. County Health Rankings reports 12,077 years of potential life lost per 100,000 (2025) — well above the national county median. 33.5% of residents in this county are flagged low-access by USDA's 2025 Food Environment Atlas — a notable supermarket-access gap. South Carolina levies a graduated state income tax (top rate 6.20%); a household at the local median AGI of $68,102 would pay roughly $2,533/year before deductions. IRS migration data (2022-2023) shows a net gain of 2,167 residents (857 households) — the ZIP's primary county is growing. Healthcare access and school options both run strong here, giving residents a wide menu of providers and enrollment choices nearby. Notable: median household income $55,972, fair market rent of $970 for a two-bedroom, and a typical home value of $235,984, up 0.6% over the past year. Every figure on this page links to its underlying federal dataset with a retrieval date so you can audit the freshness yourself.
These two readings tell a consistent story. Strong access numbers usually correlate with denser provider networks, and a high school count signals the population base that supports them. Reading them together: a household weighing this ZIP for a multi-year stay can expect both healthcare and education infrastructure to keep pace.
One concrete reading worth keeping: Depression prevalence sits near the national rate at 21.3%. Each figure on this page links to the original federal dataset with its retrieval date — this synthesis is a reading, not a substitute for the underlying records.
37.7%, which is 4.7 percentage points above the national average of 33.0% (CDC PLACES, retrieved Apr 24, 2026).
21.3%, which is 0.7 percentage points below the national average of 22.0% (CDC PLACES, retrieved Apr 24, 2026).
43.8%, which is 11.8 percentage points above the national average of 32.0% (CDC PLACES, retrieved Apr 24, 2026).
8 schools serve this ZIP, including 8 public schools (NCES CCD, retrieved Apr 27, 2026). No charter schools are listed in this ZIP by NCES CCD.
No charter schools are listed in ZIP 29020 by NCES CCD (retrieved Apr 27, 2026).
Yes, 2 high schools serve this ZIP: Camden High, Dr. Gilbert G. Woolard Technology Center. (NCES CCD, retrieved Apr 27, 2026).
22,021 people live in ZIP 29020, with a median age of 45.4 (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
$55,972 per year (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
In ZIP 29020, 76.4% of occupied housing units are owner-occupied and 23.6% are renter-occupied (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
In ZIP 29020, 5.6% of workers work from home. Public transit is used by 0.0% of commuters (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
16.9% of the population in ZIP 29020 lives below the federal poverty line (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
84.3% of households in ZIP 29020 have broadband internet access (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
The typical home value in ZIP 29020 is $235,984, up 0.6% from a year ago (Zillow Home Value Index, retrieved May 1, 2026).
Home values are up 0.6% over the past year and up 29.9% over the past five years (Zillow Home Value Index, retrieved May 1, 2026).
The average Adjusted Gross Income reported on tax returns from ZIP 29020 (Camden, SC) is $68,102 per return (IRS SOI Tax Year 2022, retrieved May 2, 2026).
Tax returns from ZIP 29020 report an average of $144 per return in real-estate tax deductions (IRS SOI Tax Year 2022, retrieved May 2, 2026).
4.3% of tax returns from ZIP 29020 (Camden, SC) report Adjusted Gross Income of $200,000 or more (IRS SOI Tax Year 2022, retrieved May 2, 2026).
As of 2022, 587 business establishments operated in ZIP 29020 employing 7,171 workers (Census ZIP Business Patterns, retrieved May 3, 2026).
The average annual pay across all local establishments in ZIP 29020 is $36,908, based on Census ZIP Business Patterns 2022 data (retrieved May 3, 2026).
According to the CDC Social Vulnerability Index (2022), ZIP 29020 ranks in the 57th percentile nationally for social vulnerability — a high vulnerability profile (retrieved May 3, 2026).
Household Characteristics is the highest-scoring CDC SVI theme for ZIP 29020, ranking in the 62th percentile nationally (CDC/ATSDR Social Vulnerability Index 2022, retrieved May 3, 2026).
FEMA has recorded 28 federal disaster declarations affecting ZIP 29020 between 1977–2026 (FEMA OpenFEMA Disaster Declarations, retrieved May 3, 2026).
Hurricane is the most common federally declared disaster type affecting ZIP 29020, accounting for 15 of 28 declarations (54%, FEMA OpenFEMA, retrieved May 3, 2026).
The most recent FEMA disaster declaration affecting ZIP 29020 was "SEVERE WINTER STORM" — a winter storm declared in 2026 (DR-3632) (FEMA OpenFEMA, retrieved May 3, 2026).
4 colleges and universities are listed near ZIP 29020 by the U.S. Department of Education College Scorecard, including Legrand Institute Of Cosmetology Inc, Denmark Technical College, and Voorhees University (retrieved May 2, 2026).
Median in-state tuition across 4 nearby institutions is $9,473 (College Scorecard, retrieved May 2, 2026).
Graduates of nearby colleges earn a median of $25,351 ten years after entry (College Scorecard, retrieved May 2, 2026).
ZIP 29020 has an average annual temperature of 62.9°F and 38.3" of annual precipitation based on the WATEREE DAM, SC US weather station 7.5 miles from the ZIP centroid (NOAA 1991–2020 Climate Normals, retrieved May 8, 2026).
Yes — ZIP 29020 is part of the Columbia, SC urbanized area, primarily served by Central Midlands Regional Transportation Authority (National Transit Database 2024, retrieved May 4, 2026).
1 hospital is located in ZIP 29020 1 is rated by CMS, with an average overall rating of 3.0 out of 5 stars (CMS Hospital Compare, 2024).
South Carolina has a graduated income tax with a top rate of 6.20%. Households at the local median AGI of $68,102 would pay roughly $2,533 in state income tax annually (estimated, before deductions). Combined sales tax: 7.49% (Tax Foundation 2025).
South Carolina runs an active paid family leave program offering up to — weeks of paid leave per year (Bipartisan Policy Center 2026).
This page covers health outcomes from CDC PLACES (40 metrics), school information from NCES CCD (8 schools), demographics from the Census ACS 5-Year (2022), home values from the Zillow Home Value Index, colleges from the U.S. Department of Education College Scorecard (4 institutions), income & tax statistics from the IRS SOI (Tax Year 2022), local business & employment from Census ZIP Business Patterns (2022), social vulnerability scores from the CDC/ATSDR SVI (2022), federal disaster declarations from FEMA OpenFEMA (28 on record), climate normals from NOAA NCEI (1991-2020), county-level crime data from the FBI Crime Data Explorer (2024), public transit coverage from the National Transit Database (2024), hospitals from CMS Hospital Compare, and state-level tax rates from the Tax Foundation. Data is refreshed on Mubboo's standard schedule.
Health data retrieved Apr 24, 2026 from CDC PLACES. School data retrieved Apr 27, 2026 from NCES CCD. Demographics retrieved Apr 30, 2026 from Census ACS 5-Year (2022). Home values retrieved May 1, 2026 from Zillow Research. College data retrieved May 2, 2026 from U.S. Dept of Education College Scorecard. Income & tax statistics retrieved May 2, 2026 from IRS SOI (Tax Year 2022). Business & employment retrieved May 3, 2026 from Census ZBP (2022). Social vulnerability scores retrieved May 3, 2026 from CDC/ATSDR SVI (2022). Federal disaster declarations retrieved May 3, 2026 from FEMA OpenFEMA (28 on record). Climate normals retrieved May 8, 2026 from NOAA NCEI (1991-2020). County-level crime data retrieved May 4, 2026 from the FBI Crime Data Explorer (2024). Transit coverage retrieved May 4, 2026 from the National Transit Database (2024). State-level tax rates retrieved 2026-05-05 15:58:22.284+00 from the Tax Foundation.
Nearby ZIPs by distance
29032 (7.6 mi) · 29175 (9.1 mi) · 29078 (Lugoff, 11.6 mi) · 29009 (Bethune, 14.9 mi) · 29128 (Boykin, 15.3 mi) · 29045 (Columbia, 15.9 mi)
Compare ZIP-level stats — population, schools, housing, climate — across nearby areas. Source: U.S. Census Bureau ZCTA basemap.
Have a specific question about ZIP 29020?
Ask Mubboo — launching Q4 2026.
Data refreshed via Mubboo's ETL pipeline; oldest source on this page retrieved Apr 24, 2026.
Social Vulnerability Index
Overall SVI
57th percentile
High Vulnerability
Based on 8 census tracts, population 22,908
Vulnerability Themes
Households Without Vehicle
465
Limited English Speakers
77
Persons with Disability
4,424
Without HS Diploma
1,936
Without Health Insurance
1,841
Adults Age 65+
5,477
The Social Vulnerability Index uses U.S. Census data to identify communities most at risk during public health emergencies and natural disasters. Higher percentiles indicate greater vulnerability. Tract-level scores are aggregated to this ZCTA via Census 2020 ZCTA→Tract crosswalk, weighted by land-area share. Source: atsdr.cdc.gov. Public domain.