Population & age
- Total population
- 8,457
- Median age
- 39.5
Sitka, AK (99835)
Sitka City and Borough · Population 8,457
Fresh.Data current as of Apr 24, 2026
Sitka, AK (ZIP 99835) sits in Sitka City and Borough. The page draws on 2 federal data feeds retrieved Apr 27. Top health signal: Annual Checkup comes in above the national average at 68.4%. NCES lists 7 schools serving the area, 7 non-charter. 1 college or university serves the area, with median in-state tuition of $7,056. IRS data shows average household income (AGI) of $89,473, well above the ~$45K national average per return. Biological accounts for 100% of the 2 FEMA disaster declarations on record for this ZIP. Annual average temperature is just 44.1°F per NOAA's 1991–2020 Climate Normals — a notably cold-weather climate. 34.5% of residents in this county are flagged low-access by USDA's 2025 Food Environment Atlas — a notable supermarket-access gap. Alaska has no state income tax, saving the local median household (AGI $89,473) approximately $4,116/year vs the US average effective state tax rate. Healthcare access is the area's quieter strength; school options sit on the lighter side, so families may find themselves looking at districts a few ZIPs over. Notable: median household income $95,261, fair market rent of $1,570 for a two-bedroom, and a typical home value of $484,597, down 0.3% 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.
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Demographics
Race & ethnicity
- White
- 62.3%
- Black
- 0.7%
- Asian
- 7.9%
- Hispanic / Latino
- 7.4%
- Other / multi-racial
- 18.6%
Income & housing
- Median household income
- $95,261
- Median home value
- $424,700
Education
- Bachelor's degree or higher (age 25+)
- 32.1%
Employment
- Unemployment rate
- 5.0%
Housing
- Owner-occupied
- 2,231(64.5%)
- Renter-occupied
- 1,228(35.5%)
- Vacant units
- 621
- Built (median)
- 1978
Commute
- Public transit
- 12(0.3%)
- Work from home
- 317(6.8%)
- Avg commute
- 10.7 min
Economic wellbeing
- Below poverty line
- 571(6.9%)
- Uninsured
- 218(2.6%)
Digital access
- Broadband access
- 3,019(87.3%)
- No broadband
- 440(12.7%)
Language & nativity
- Foreign-born
- 853(10.1%)
- Non-English at home
- 1,203(14.9%)
Fair Market Rent
Fresh.HUD SAFMR · May 1, 2026Studio
$1,100
/month
1 Bed
$1,350
/month
2 Bed
$1,570
/month
3 Bed
$2,180
/month
4 Bed
$2,630
/month
HUD Fair Market Rents represent the 40th percentile of standard-quality rental housing in this area. FY2026 data.
Home values
Typical home value
$484,597
Zillow Home Value Index (ZHVI) · as of March 2026
Year-over-year change
-0.3%
vs. March 2025
5-year change
-6.0%
vs. March 2021
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 construction
New housing units permitted
11
Across 11 permitted buildings. Total construction value: $2.4M.
Single-family
11
100% of total units
Multifamily (2+ unit)
0
0% of total units
Single-family value
$2.4M
construction value
Multifamily value
$0
construction value
Based on county-level data (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.
Income & tax statistics
Tax returns filed
4,500
Average AGI
$89,473
Avg property tax
$170
EITC participation
7.6%
Income distribution
- $1 – $25,00023.1% · 1,040
- $25,000 – $50,00022.2% · 1,000
- $50,000 – $75,00017.1% · 770
- $75,000 – $100,00011.1% · 500
- $100,000 – $200,00020.2% · 910
- $200,000 or more6.2% · 280
Avg mortgage interest
$402
Avg charitable contribution
$508
Avg capital gains
$5,126
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 $402.6M across all reported brackets.
Business & employment
Business establishments
383
Total employment
2,938
Annual payroll
$186.6M
Average annual pay
$63,503
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.
Employment & wages
Average annual pay
$61,555
Average weekly wage
$1,184
Total employment
4,479
Total establishments
413
That is roughly 6% 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
Unemployment rate
3.1%
That is 0.9 percentage points below the US national unemployment rate of about 4.0%.
Labor force
4,580
Employed
4,438
Unemployed
142
Based on Sitka Borough/city, AK 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.
Banking access
FDIC-insured bank branches
4
Typical banking access
A standard suburban / mid-density branch count for this area.
Total deposits
$312.5M
across all branches in this ZIP
Distinct institutions
4
different banks operating here
Top banks by deposits in this ZIP
- 1.Wells Fargo Bank, National Association$94.8M · 1 branch
- 2.First National Bank Alaska$87.1M · 1 branch
- 3.First Bank$73.7M · 1 branch
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.
Hospitals & healthcare facilities
Facilities located inside ZIP 99835 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)
SOUTHEAST ALASKA REGIONAL HEALTH CONSORTIUM
★★★★★3.0
Critical Access Hospitals
Tribal
Emergency services
222 TONGASS DR, SITKA, AK, 99835
Source: Centers for Medicare & Medicaid Services Provider Data (data.cms.gov). Public domain.
Public libraries
Public-library outlets
1
Single library outlet
One public-library outlet serves this ZIP — typical of suburban and small-town areas. Card holders also have full access to the rest of the system's branches.
Buildings
1
1 central
Avg hours / week
46
across outlets in this ZIP
Avg square feet
9,920
per outlet
Outlets in this ZIP
- 1.Sitka Public Library
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.
Federal Disaster Declarations
Federally Declared Disasters
2
Date Range
2020
Most Recent Declaration
COVID-19 PANDEMIC
Biological — declared April 9, 2020 (DR-4533)
Incident period: January 20, 2020 – May 11, 2023
Top Incident Types
- Biological2 (100%)
Households Program
1
Housing & temporary lodging support
Public Assistance
2
Repair of public facilities & roads
Hazard Mitigation
1
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.
Climate
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
44.1°F
39.4° – 48.8°
Annual precipitation
245.7"
Annual snowfall
101.8"
Heating · cooling days
7,600.4 · 0.6
Annual base 65°F
Nearest station: LITTLE PORT WALTER, AK US, 42.5 miles from the centroid of Sitka, AK (ZIP 99835)
Source: NOAA National Centers for Environmental Information, 1991–2020 U.S. Climate Normals (ncei.noaa.gov). Public domain.
Community health profile
Years of potential life lost (per 100K)
7,687
That is roughly 513 years per 100,000 below 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
15%
of adults self-report
Poor physical health days
3.9
avg per adult per month
Poor mental health days
5.1
avg per adult per month
Uninsured
14.9%
of residents under 65
Primary care MDs
214
per 100,000 residents
Preventable hospital stays
2,905
per 100K Medicare enrollees
Food environment (0-10)
8.4
10 = best access & security
Exercise access
100%
residents near a facility
Flu vaccinated
41%
of Medicare enrollees
Low birth weight (under 2,500 g) accounts for 4.5% of live births in this county — an early-life health input that downstream outcomes track against.
Based on Sitka 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
Food access status
Significant food access concerns
34.5% of Sitka County, AK residents live more than 1 mile (urban) or 10 miles (rural) from the nearest supermarket.
Grocery stores
0.36
per 1,000 residents
Supercenters & clubs
—
per 1,000 residents
SNAP-authorized stores
0.47
accepting food benefits
Fast-food restaurants
0.36
per 1,000 residents
Among low-income residents, 6.3% 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 Sitka County, AK 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).
Who’s moving in and out
Net migration (2022-2023)
▲+5 people
+66 households • −$1.4M net AGI flow
Moved in
577households
931 people • $33.6M AGI
Moved out
511households
926 people • $35.0M AGI
Where new residents came from
No county-level breakdown available.
Where departing residents went
- Anchorage Municipality, AK — 20 households
Incoming households reported an average AGI of $58,272 versus departing households' $68,466.
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.
Taxes & benefits in Alaska
State-level rules that apply to every resident of ZIP 99835. Numbers reflect the most recent published year per source.
Tax rates
Income tax
None
No state income tax
Sales tax (combined)
1.82%
State 0.00% · avg local 1.82%
Property tax (effective)
0.86%
Median $757/year
Tax burden rank
1 of 50
5.60% of personal income
For ZIP 99835: A household at this ZIP's median AGI of $89,473 keeps approximately $4,116 more annually than residents of the typical income-tax state. Applied to this ZIP's typical home value of $484,597, that works out to roughly $4,178/year in property tax.
Paid family leave
Program
No program
No program
Safety net
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).
Data sources used on this page
SourcesFresh.CDC PLACES · Apr 24, 2026Fresh.NCES CCD via Urban Institute EDP · Apr 27, 2026Fresh.HUD SAFMR · May 1, 2026
All data on this page is sourced from federal government datasets · Not AI-generated · Methodology
Health profile
Crude prevalence estimates from CDC PLACES, derived from BRFSS small-area modeling. Population-level figures only.
Obesity
30.1%
2.9pp below the 33.0% national rate.
High Blood Pressure
33.0%
Tracks close to the 32.0% national rate.
Depression
19.7%
2.3pp below the 22.0% national rate.
Annual Checkup
68.4%
7.6pp below the 76.0% national rate.
Health Insurance
8.5%
4.5pp below the 13.0% national rate.
Diabetes
9.6%
Tracks close to the 11.0% national rate.
Schools in this ZIP
7 schools serve this ZIP, including 7 non-charter.
| School | Type | Grades | Enrollment |
|---|---|---|---|
| Mt. Edgecumbe High School | Public | 9–12 | 374 |
| Sitka High School | Public | 9–12 | 316 |
| Keet Gooshi Heen Elementary | Public | 2–5 | 303 |
| Blatchley Middle School | Public | 6–8 | 277 |
| Baranof Elementary | Public | -1–1 | 142 |
Showing top 5 by enrollment. 2 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 & universities nearby
Colleges in this area
1
Median in-state tuition
$7,056
Median earnings (10 yr)
$48,475
- 4-Year
University of Alaska Southeast
Juneau, AK · 99801
- In-state tuition
- $7,056
- Out-of-state tuition
- $20,640
- Acceptance rate
- 63.3%
- Graduation rate
- 29.5%
- Median earnings (10 yr)
- $48,475
- Median student debt
- $19,111
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.
What these numbers say together
Sitka, AK (ZIP 99835) sits in Sitka City and Borough. The page draws on 2 federal data feeds retrieved Apr 27. Top health signal: Annual Checkup comes in above the national average at 68.4%. NCES lists 7 schools serving the area, 7 non-charter. 1 college or university serves the area, with median in-state tuition of $7,056. IRS data shows average household income (AGI) of $89,473, well above the ~$45K national average per return. Biological accounts for 100% of the 2 FEMA disaster declarations on record for this ZIP. Annual average temperature is just 44.1°F per NOAA's 1991–2020 Climate Normals — a notably cold-weather climate. 34.5% of residents in this county are flagged low-access by USDA's 2025 Food Environment Atlas — a notable supermarket-access gap. Alaska has no state income tax, saving the local median household (AGI $89,473) approximately $4,116/year vs the US average effective state tax rate. Healthcare access is the area's quieter strength; school options sit on the lighter side, so families may find themselves looking at districts a few ZIPs over. Notable: median household income $95,261, fair market rent of $1,570 for a two-bedroom, and a typical home value of $484,597, down 0.3% 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.
The two domains pull in different directions. Healthcare access reads strong, but the on-paper school count is on the lighter side — that’s less a quality signal and more a density one. Households here often look at districts a few ZIPs over for school choice while keeping their providers local.
One concrete reading worth keeping: Depression prevalence sits lower the national rate at 19.7%. 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.
Frequently Asked Questions — ZIP 99835
What is the obesity rate in ZIP 99835?
30.1%, which is 2.9 percentage points below the national average of 33.0% (CDC PLACES, retrieved Apr 24, 2026).
What is the depression rate in ZIP 99835?
19.7%, which is 2.3 percentage points below the national average of 22.0% (CDC PLACES, retrieved Apr 24, 2026).
What is the high blood pressure rate in ZIP 99835?
33.0%, which is 1.0 percentage points above the national average of 32.0% (CDC PLACES, retrieved Apr 24, 2026).
How many schools are in ZIP 99835?
7 schools serve this ZIP, including 7 public schools (NCES CCD, retrieved Apr 27, 2026). No charter schools are listed in this ZIP by NCES CCD.
Does ZIP 99835 have charter schools?
No charter schools are listed in ZIP 99835 by NCES CCD (retrieved Apr 27, 2026).
Are there high schools in ZIP 99835?
Yes, 4 high schools serve this ZIP: Mt. Edgecumbe High School, Sitka High School, Sitka Reach, and 1 more. (NCES CCD, retrieved Apr 27, 2026).
What is the population of ZIP 99835?
8,457 people live in ZIP 99835, with a median age of 39.5 (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
What is the median household income in ZIP 99835?
$95,261 per year (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
Is ZIP 99835 mostly renters or homeowners?
In ZIP 99835, 64.5% of occupied housing units are owner-occupied and 35.5% are renter-occupied (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
How do people commute in ZIP 99835?
In ZIP 99835, 6.8% of workers work from home. Public transit is used by 0.3% of commuters (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
What is the poverty rate in ZIP 99835?
6.9% of the population in ZIP 99835 lives below the federal poverty line (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
What percentage of households in ZIP 99835 have broadband internet?
87.3% of households in ZIP 99835 have broadband internet access (Census ACS 5-Year 2022, retrieved Apr 30, 2026).
What is the typical home value in ZIP 99835?
The typical home value in ZIP 99835 is $484,597, down 0.3% from a year ago (Zillow Home Value Index, retrieved May 1, 2026).
Are home values rising or falling in ZIP 99835?
Home values are down 0.3% over the past year and down 6.0% over the past five years (Zillow Home Value Index, retrieved May 1, 2026).
What is the average household income in ZIP 99835?
The average Adjusted Gross Income reported on tax returns from ZIP 99835 (Sitka, AK) is $89,473 per return (IRS SOI Tax Year 2022, retrieved May 2, 2026).
How much do homeowners pay in property tax in ZIP 99835?
Tax returns from ZIP 99835 report an average of $170 per return in real-estate tax deductions (IRS SOI Tax Year 2022, retrieved May 2, 2026).
What percentage of residents in ZIP 99835 earn over $200,000?
6.2% of tax returns from ZIP 99835 (Sitka, AK) report Adjusted Gross Income of $200,000 or more (IRS SOI Tax Year 2022, retrieved May 2, 2026).
How many businesses are in ZIP 99835?
As of 2022, 383 business establishments operated in ZIP 99835 employing 2,938 workers (Census ZIP Business Patterns, retrieved May 3, 2026).
What is the average salary in ZIP 99835?
The average annual pay across all local establishments in ZIP 99835 is $63,503, based on Census ZIP Business Patterns 2022 data (retrieved May 3, 2026).
How vulnerable is ZIP 99835 to disasters and public health emergencies?
According to the CDC Social Vulnerability Index (2022), ZIP 99835 ranks in the 61th percentile nationally for social vulnerability — a high vulnerability profile (retrieved May 3, 2026).
What is the biggest vulnerability factor in ZIP 99835?
Housing Type & Transportation is the highest-scoring CDC SVI theme for ZIP 99835, ranking in the 84th percentile nationally (CDC/ATSDR Social Vulnerability Index 2022, retrieved May 3, 2026).
How many federally declared disasters has ZIP 99835 experienced?
FEMA has recorded 2 federal disaster declarations affecting ZIP 99835 between 2020 (FEMA OpenFEMA Disaster Declarations, retrieved May 3, 2026).
What kinds of disasters most often hit ZIP 99835?
Biological is the most common federally declared disaster type affecting ZIP 99835, accounting for 2 of 2 declarations (100%, FEMA OpenFEMA, retrieved May 3, 2026).
What was the most recent disaster declared for ZIP 99835?
The most recent FEMA disaster declaration affecting ZIP 99835 was "COVID-19 PANDEMIC" — a biological declared in 2020 (DR-4533) (FEMA OpenFEMA, retrieved May 3, 2026).
What colleges are near ZIP 99835?
1 college or university is listed near ZIP 99835 by the U.S. Department of Education College Scorecard, including University Of Alaska Southeast (retrieved May 2, 2026).
What is the average tuition at colleges near ZIP 99835?
Median in-state tuition across 1 nearby institution is $7,056 (College Scorecard, retrieved May 2, 2026).
What do graduates earn from colleges near ZIP 99835?
Graduates of nearby colleges earn a median of $48,475 ten years after entry (College Scorecard, retrieved May 2, 2026).
What is the climate like in ZIP 99835?
ZIP 99835 has an average annual temperature of 44.1°F and 245.7" of annual precipitation based on the LITTLE PORT WALTER, AK US weather station 42.5 miles from the ZIP centroid (NOAA 1991–2020 Climate Normals, retrieved May 8, 2026).
What hospitals are in ZIP 99835?
1 hospital is located in ZIP 99835 1 is rated by CMS, with an average overall rating of 3.0 out of 5 stars (CMS Hospital Compare, 2024).
What taxes apply in ZIP 99835?
Alaska has no state income tax. For a household earning the local median AGI of $89,473, this saves approximately $4,116 per year compared to the national average effective state tax rate. The combined state and local sales tax rate is 1.82% (Tax Foundation 2025).
Does Alaska have paid family leave?
Alaska has no state paid family leave program (Bipartisan Policy Center 2026).
What data is available for ZIP 99835?
This page covers health outcomes from CDC PLACES (40 metrics), school information from NCES CCD (7 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 (1 institution), 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 (2 on record), climate normals from NOAA NCEI (1991-2020), hospitals from CMS Hospital Compare, and state-level tax rates from the Tax Foundation. Data is refreshed on Mubboo's standard schedule.
How current is this data?
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 (2 on record). Climate normals retrieved May 8, 2026 from NOAA NCEI (1991-2020). State-level tax rates retrieved 2026-05-05 15:58:22.284+00 from the Tax Foundation.
More Info topics
Have a specific question about ZIP 99835?
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
61st percentile
High Vulnerability
Based on 2 census tracts, population 8,462
Vulnerability Themes
Households Without Vehicle
362
Limited English Speakers
72
Persons with Disability
1,134
Without HS Diploma
290
Without Health Insurance
987
Adults Age 65+
1,375
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.