he data included in the index is drawn from publicly available sources that are up to date at a census-tract level statewide for California. In order to be included in the index, this data is also required to be demonstrably linked/in correlation with life expectancy, and to be actionable in some way (e.g. policy).
These sources included:
1. U. S. Census Bureau's American Community Survey (ACS)
2. California Environmental Protection Agency (CalEPA)
3. US Department of Housing and Urban Development (HUD)
4. Green Info, (parks)
5. The National Land Cover Database, (tree canopy)
6. US Department of Food and Agriculture (supermarket access)
7. US Environmental Protection Agency (retail density)
8. University of California, Berkeley (voter participation)
Virginia Commonwealth University also provided access to their analysis of life expectancy at the California census tract level.
