Social Vulnerability Index (SoVI)

Methodology

This indicator reports information from the Centers for Disease Control and Prevention Social Vulnerability Index (CDC SVI or SVI). The SVI is a score based on 16 U.S. census variables from the 5-year American Community Survey (ACS) to identify communities that may need support before, during, or after disasters. These variables are grouped into four themes that cover four major areas of social vulnerability and then combined into a single measure of overall social vulnerability. The four areas are:

• Socioeconmic Status
• Household Characteristics
• Racial & Ethnic Minority Status
• Housing Type and Transportation

About the Social Vulnerability Index (SVI)
The degree to which a community exhibits certain social conditions, including high poverty, low percentage of vehicle access, or crowded households, may affect that community’s ability to prevent human suffering and financial loss in the event of disaster. These factors describe a community’s social vulnerability.

The Geospatial Research, Analysis & Services Program (GRASP) created the Centers for Disease Control and Prevention Social Vulnerability Index to help public health officials and emergency response planners identify and map the communities that will most likely need support before, during, and after a hazardous event. SVI indicates the relative vulnerability of every U.S. Census tract. Census tracts are subdivisions of counties for which the Census collects statistical data. SVI ranks the tracts on 16 social factors, including unemployment, minority status, and disability, and further groups them into four related themes. Thus, each tract receives a ranking for each Census variable and for each of the four themes, as well as an overall ranking. In addition to tract-level rankings, SVI 2010, 2014, 2016, 2018,2020 and 2022 also have corresponding rankings at the county level. Notes below that describe “tract” methods also refer to county methods. How can CDC SVI help communities be better prepared for hazardous events? SVI provides specific socially and spatially relevant information to help public health officials and local planners better prepare communities to respond to emergency events such as severe weather, floods, disease outbreaks, or chemical exposure.