County formula: county = state × fc where
fc = county median rent ÷ state avg median rent (housing-correlated KPIs); for D1 Pump,
AAA county price ÷ state avg AAA price when scrape live.
State Index: population-weighted avg of county indices (ACS B01003).
Tag wins: LIVE → PROXY-REGION → PROXY-COUNTY-ADJ → PROXY-STATE-FLAT → SYNTH. Never silent.
TCBI_2026.7_v3.2.0_publication_eiarefreshv2.0_neighborhood_liveseed (LA proof-of-concept)Tract formula: tract = state × tract_fc where
tract_fc = tract median rent ÷ state avg median rent (clamped [0.7, 1.5]).
For Pump: tract_fpump = 1 + 0.5×(tract_fc−1) (damped).
Lazy-load: Tract TopoJSON + ACS data load only when "Show neighborhoods" clicked. Cached per county.
MOE: ACS tract margins of error displayed as halos when value/MOE < 5.
Scope: 15 mega-counties only (>1.5M pop). Other 3,119 counties stay county-level.
National choropleth covering all 50 states, DC, and 3,142 counties. Tract resolution (Census ACS5 2023) for 15 mega-counties covering ~17% of US population: Los Angeles, Cook (Chicago), Harris (Houston), Maricopa (Phoenix), San Diego, Orange, Miami-Dade, Dallas, Riverside, King (Seattle), Clark (Las Vegas), Tarrant (Fort Worth), Bexar (San Antonio), Broward, Wayne (Detroit). Plus 262 NYC Neighborhood Tabulation Areas (NYC DCP 2020) across all 5 boroughs.
| Series | Identifier | Used for |
|---|---|---|
| Census ACS5 2023 — Median Gross Rent | B25064_001E | tract_fc at tract level; state baselines |
| Census ACS5 2023 — Median Household Income | B19013_001E | Income-share KPI · NTA pop-weighted means |
| Census ACS5 2023 — Total Population | B01003_001E | Pop-weighted state/NTA aggregations |
| EIA Weekly Retail Gasoline | state series via api.eia.gov | D1 Pump state values · 9 states direct |
| BLS Average Price Data | APU regional series | D2 Pantry · BLS APU 7-item × 4 regions |
| BLS APU Mediterranean basket | 10 LIVE BLS series + 7 SYNTH anchors | D3 Plate · weekly fam-of-4 cost |
| BLS CPI Food Away From Home | CUUR0000SEFV | D4 Restaurant · national series |
| USDA Thrifty Food Plan Sept 2024 | FNS public reference | D3 Plate calibration reference |
| us-atlas counties-10m.json | npm us-atlas@3 | National/state choropleth geometry |
| loganpowell/census-geojson 2020 cb_500k | raw GitHub mirror via jsdelivr | Tract polygons (LA + 14 other mega-counties) |
| NYC DCP Neighborhood Tabulation Areas 2020 | NYC Open Data 9nt8-h7nd | 262 NYC NTA polygons |
tract_value = state_baseline × tract_fc
where tract_fc = tract_median_rent / state_avg_median_rent, clamped to [0.7, 1.5] to prevent extreme outliers.
For D1 Pump (non-housing-correlated), uses a damped factor: tract_fpump = 1 + 0.5 × (tract_fc − 1).
TCBI Composite weighting (D5): 0.4 × pump-component + 0.6 × housing-correlated component, applied at every resolution.
NTAs are not Census tabulation units. We aggregate tract-level ACS5 values up to NTA via point-in-polygon (tract centroid in NTA boundary), pop-weighted mean: 2,293 of 2,324 NYC tracts mapped (98.7% coverage). Suppressed tracts inherit county value.
LIVE-EIA-STATE Direct EIA state-level series
LIVE-BLS-REGION Direct BLS regional APU value
LIVE-ACS-TRACT Direct Census ACS5 tract value
PROXY-PADD/REGION State inherits PADD or Census region value
PROXY-COUNTY-ADJ County via rent ratio fc
PROXY-TRACT-ADJ Tract via tract rent ratio (clamped 0.7-1.5)
COUNTY-LEVEL No tract data exists — tract inherits county value
DATA-SUPPRESSED ACS small-N suppression — falls back to county avg
TCBI-TRACT-DERIVED Composite at tract via weighted formula
Census ACS5 2023 covers 2019-2023 conditions, released by Census in December 2024. BLS APU/CPI series are monthly, current to 2026-M03 in this build. EIA gas is weekly, current to 2026-05-04.
• D4 Restaurant (BLS CPI Food Away From Home) has no published tract-level series; tract inherits county value flat.
• Clamps at fc ∈ [0.7, 1.5] produce visually-flat regions in very-low-rent or very-high-rent areas — intentional limit on baseline extrapolation.
• 72 of 2,498 LA tracts (~3%) had suppressed rent data; they fall back to CA state composite.
• Place mid-tier uses 177 curated seed centroids with Voronoi tessellation. Real TIGER PLACE polygons deferred.