Census tracts are the preferred unit of analysis compared to ZIP codes. They are designed to have a homogenous population with an average of 4,000 people. The tracts are established as consistent blocks of geography that remain stable over a 10-year period. Every decennial, the U.S. Census Bureau updates census tract boundaries to coincide with the updated population figures. The Community Dashboard displays data in 5-year increments. Data from 2007-2011 through 2015-2019 use 2010 census tract boundaries. Data for 2016-2020 and forward use 2020 census tract boundaries.
ZIP codes are created for use by the U.S. Postal Service for mail delivery purposes. The boundaries of a ZIP code may not be based on population characteristics. The population within ZIP codes is not the same for every ZIP code. Additionally, the ZIP code numbering system is constantly changing to facilitate the delivery of mail. ZIP codes may span over county boundaries. In the FLHealthCHARTS Community Map, ZIP codes that include areas in more than one county will report just the count or rate from the chosen county.
Use caution when interpreting rates based on small numbers of events. Rates are considered unstable if they are based on fewer than 5 events or if the denominator (population at risk) is fewer than 20.
Quartiles are calculated by ranking counties or subcounty regions in order. These groups are then divided into four parts with each quartile representing approximately 25% of the counties or subcounty regions.
Green, yellow, orange and red county quartiles represent the most to the least favorable situation (1st to 4th quartile). Light to dark blue county quartiles represent density from lowest to highest (1st to 4th).
Birth data are for resident live births. Death data are for resident deaths.