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Methodology

Gera Coverage Gap Score (GCGS)

The GCGS is a per-demographic, per-state index of health insurance coverage gaps derived from real 2023 American Community Survey 1-year estimates (US Census Bureau, public domain). It expresses each state's uninsured rate as a percentage of the national average for the same demographic band. GCGS 100 = exactly the national average; higher = wider gap.

Formula

GCGS = round( state_uninsured_rate ÷ national_uninsured_rate × 100 )
  • state_uninsured_rate — real ACS estimate for the state × demographic band (%)
  • national_uninsured_rate — real ACS estimate for the US × same demographic band (%)
  • Result interpretation: 100 = national average · >100 = wider gap · <100 = narrower gap

Step-by-step reproduction

  1. 1

    Obtain the real ACS uninsured rate for the demographic band

    Fetch the relevant ACS B-table percentage for the state and demographic. Age bands: B27001. Employment bands: B27011. Poverty-ratio bands: B27016. All tables are key-free via the Census Reporter API (public domain). E.g. Alabama working-age (19–64) uninsured = 12.3% from B27001.

  2. 2

    Obtain the matching national (US) uninsured rate

    Fetch the same B-table variable for geo_id 01000US (United States). E.g. US working-age uninsured 2023 = 11.3% (matches ACSBR-024 published figure).

  3. 3

    Compute the Gera Coverage Gap Score (GCGS)

    GCGS = round(state_rate / national_rate × 100). 100 = exactly the national average. >100 = a wider coverage gap than the US average. <100 = a narrower gap. Example: Texas working-age uninsured 21.6% ÷ US 11.3% × 100 = GCGS 191 (far above national).

  4. 4

    Apply to all 51 state + DC rows and all demographic bands

    Repeat steps 1–3 for each state and each of the nine demographic bands: under 19, working-age 19–64, seniors 65+, below-138%-poverty (19–64), 138–399%-poverty (19–64), 400%+-poverty (19–64), employed, unemployed, not in labor force. Produces 51 × 9 = 459 GCGS values in total.

  5. 5

    Verify against published figures

    Cross-check national rates: under-19 6.0% and working-age 11.3% match ACSBR-024 (US Census Bureau, September 2024). Texas under-19 13.6% and Massachusetts under-19 2.1% also match published report.

Data sources

Tables used (all 2023 ACS 1-year estimates, US Census Bureau):

  • B27001 — Health Insurance Coverage Status by Sex by Age (age-band uninsured rates)
  • B27011 — Health Insurance Coverage Status by Work Experience (employment-band rates for 19–64 year olds)
  • B27016 — Health Insurance Coverage Status by Ratio of Income to Poverty Level (poverty-ratio bands)

Fetched key-free via Census Reporter API (open-source project using the Census Bureau's Community Data Profile API). US federal government works are in the public domain (17 U.S.C. §105).

National baselines (2023)

US national uninsured rates by demographic band — 2023 ACS
Demographic bandNational uninsured rateNote
Children under 196.0%Matches ACSBR-024
Working-age adults 19–6411.3%Matches ACSBR-024
Seniors 65 and older0.8%Nearly universal Medicare
Below 138% poverty (19–64)21.1%Medicaid eligibility threshold
138–399% poverty (19–64)14.9%Marketplace subsidy range
400%+ poverty (19–64)5.0%Higher-income adults
Employed workers (19–64)10.0%Many uninsured despite employment
Unemployed workers (19–64)24.3%Much higher gap
Not in labor force (19–64)14.1%

Example: widest working-age coverage gaps

Top 5 states by working-age GCGS — 2023 ACS
StateUninsured (19–64)GCGS
Texas21.6%191
Georgia16.5%146
Oklahoma15.9%141
Florida15.5%137
Nevada15.5%137

All from real 2023 ACS 1-year estimates. US average = 11.3% (GCGS 100).

Frequently asked questions

What does a GCGS of 200 mean?
A GCGS of 200 means the uninsured rate for that demographic in that state is twice the national average for that same demographic. GCGS 100 = exactly the US average; 50 = half the national rate (much better than average); 150 = 50% above the national rate.
Why are there different GCGS values per band for the same state?
Insurance coverage gaps affect demographic groups very differently. A state may have a low uninsured rate for children (thanks to Medicaid/CHIP) but a high rate for working-age adults near the poverty threshold who fall in the Medicaid expansion gap. The per-band GCGS makes these disparities visible.
What ACS tables does the GCGS use?
B27001 (sex × age × insurance status) for age bands; B27011 (labor-force status × insurance) for employment bands; B27016 (poverty-ratio × age × insurance) for income/poverty bands. All are 2023 ACS 1-year estimates, US Census Bureau, public domain.
Is the GCGS the same as the Census uninsured rate?
No. The ACS uninsured rate is the raw percentage. The GCGS is an index that re-expresses that percentage relative to the US national rate for the same demographic band. It makes cross-state comparisons within a demographic easier to interpret at a glance.
How often is the GCGS updated?
The underlying ACS 1-year estimates are released annually in September. This cluster was last updated on 2026-06-20 using 2023 data. The next update will incorporate 2024 data when available (September 2024).

Contains public sector information published by US Census Bureau and licensed under the Public domain (US federal government work, 17 U.S.C. §105). Source: US Census Bureau — 2023 American Community Survey 1-Year Estimates (Tables B27001, B27011, B27016) (2023, published September 2024).

Licence: Public domain (US federal government work, 17 U.S.C. §105) https://www.usa.gov/government-works

Informational/educational only — not a substitute for professional medical advice; a clinician interprets results.