CDC Social Vulnerability Index

CDC Social Vulnerability Index

CDC Social Vulnerability Index ranks census tracts on 16 social factors across 4 themes: Socioeconomic Status, Household Characteristics, Racial/Ethnic Minority Status, Housing Type/Transportation. Overall SVI score 0-1 (higher = more vulnerable). Data years: 2000, 2010, 2014, 2016, 2018, 2020, 2022. ArcGIS FeatureServer with query parameters. Key fields: RPL_THEMES (overall rank), RPL_THEME1-4 (theme ranks), E_TOTPOP (population), ST_ABBR (state).

Data Model

• Overall SVI — RPL_THEMES: percentile ranking 0-1 across all 16 variables. Higher = more vulnerable.
• Theme 1 (Socioeconomic) — RPL_THEME1: below poverty, unemployed, housing cost burden, no health insurance, no high school diploma.
• Theme 2 (Household) — RPL_THEME2: aged 65+, aged 17 and under, civilian with disability, single-parent households, English language proficiency.
• Theme 3 (Racial/Ethnic) — RPL_THEME3: minority status and English language proficiency.
• Theme 4 (Housing/Transportation) — RPL_THEME4: multi-unit structures, mobile homes, crowding, no vehicle, group quarters.
• Flags — F_THEMES (overall flag), F_THEME1-4: binary flags where 1 = top 10% most vulnerable.

Query Syntax (ArcGIS)

• where — SQL-like filter (e.g. ST_ABBR='CA', RPL_THEMES>=0.9).
• outFields — field list or * for all.
• resultRecordCount — max records per request.
• f — output format, use json.
• returnGeometry — set to false for faster tabular queries.
• orderByFields — sort expression (e.g. RPL_THEMES DESC).

Gotchas

• No auth required: Public ArcGIS FeatureServer.
• Score interpretation: 0 = least vulnerable, 1 = most vulnerable. Scores are percentile ranks, not absolute measures.
• Data year in service name: CDC_SVI_2022 for 2022 data. Change the year in the URL for other vintages.
• Result limit: Default max 2000 records; use resultOffset for pagination.
• Negative values: -999 indicates suppressed data (insufficient population or data quality).