Population

The total population is the estimated number of people who live in a particular area. It includes estimates for all males, females, adults and children. The estimate presented here is from the 2010 Census (Redistricting Data SF).

Households

A household includes all the people who occupy a housing unit as their usual place of residence. For example, there might be four people in a family living in one house. This would count as four people under population, but only as one household. The estimate presented here is from the 2010 Census (Redistricting Data SF).

Population Density

Population density is the number of people per square mile. The higher the population density, the more concentrated the people are living near each other. The lower the population density, the more spread out they are living. This indicator can help you understand whether an area is more urban or rural in nature. For example, in 2010, the population density of a highly urbanized city like New York was approximately 26,803 persons per square mile whereas in a lower density city like Tampa the value was approximately 1,862 persons per square mile.

It is important to understand the population, number of households and population density because it can help to explain the needs and characteristics of a community. It can help to describe whether there are or are not a lot of people living in a particular area. It can also show whether people are living close together in a densely populated community or further apart in a more sparsely populated community.

Total Population and Households:

Every ten years the U.S. Census Bureau conducts its official population count of the United States (referred to as the Decennial Census). The most recent census was conducted in 2010. The U.S. Census Bureau collects this data in two ways. They first send out a mail-in census form. For those people who do not return their mail-in forms, the Census Bureau sends people to those homes to administer the form in person.

There are two census forms used during the Decennial Census. The first is the short-form, which is asked of every person and housing unit in the United States. On this form are a limited number of questions (Age, Hispanic or Latino origin, Household Relationship, Home Ownership, Number of People, Race, and Sex). The second is the American Community Survey (ACS), which is given to a sample of the population to ask more detailed questions on population, housing, and other social and economic characteristics. The information collected in the ACS is then estimated for the entire population annually.

The data from the short and ACS forms are made public through the U.S. Census Bureau.
Source: U.S. Census – Factfinder

Total Population and Households: The data presented on the Community Atlas come from the U.S. Census Bureau's Redistricting Data SF and Summary File 1, which have information primarily collected through the short form. For details on the methods used by the Census Bureau, please see their technical documentation:

• Summary File 1: Technical Documentation


• Redistricting Data: Guide to Redistricting Data

The following data tables are used:

Total Population: Redistricting Data SF, P1. Total Population
Total Households: Redistricting Data SF, H1. Occupancy Status.

For the Community Atlas, demographic totals were calculated for specific areas (neighborhoods and communities) by using the dasymetric method. This is done by reapportioning the data we receive for one type of geographic boundary (Census tracts, Census block groups, zip codes, etc.) to the neighborhood and community boundaries. The method used for this process is a modified version of the dasymetric mapping technique outlined in the following studies:

• Dasymetric Mapping Techniques for the San Francisco Bay prepared by Rachel Sleeter of the U.S. Geological Survey
• Generating Surface Models of Population Using Dasymetric Mapping by Jeremy Mennis published in The Professional Geographer in 2003.

The basic steps taken for reapportioning the data:

• Land-use classifications (Southwest Florida Water Management District, 2009) were used to eliminate uninhabited areas from the data source boundaries (Census tracts, Census block groups, zip codes, etc.)
• Neighborhood and Community data values were generated by extracting data values from the data source boundaries (Census tracts, Census block groups, zip codes, etc.) based on the percentage of that boundary area that fell within the neighborhood or community boundary. Using only the inhabited area for this process instead of total area would allow for a more realistic representation when reapportioning the data to neighborhood or community.

Population Density: Population density is calculated using population numbers from the U.S. Census and dividing it by the area calculated from each designated boundary (neighborhood, community, municipality and county).

Total Population/Area in square miles = Population Density

When using these data, please consider the following:

• We chose Census 2010 data to include on the Community Atlas because it is most appropriate for smaller geographic areas such as neighborhoods. More current population estimates, such as those from the American Community Survey (ACS), are typically for a county or city as a whole, not communities or neighborhoods. If you choose to use this data, please keep in mind that it is an estimate.
• The data presented are from the 2010 Redistricting Data SF and Summary File 1 which were based on an attempt to count all citizens. This methodology has generally been well received with a higher than expected mail-in response rate of 72 percent. Additional information on the Census 2010 methodology can be found on the Census Bureau website.
• The data has been reapportioned from the original boundaries provided to us in order to develop estimates for neighborhoods and communities. This has been done because not all data is reported for the same boundaries as the neighborhoods and communities on the Community Atlas. When using these data, view them as estimates for these neighborhoods and communities.
• Population density is estimated as the number of people per square mile. This is done to allow for a comparison between completely different areas of the world. Since this is a standard calculation, it is possible that a particular neighborhood or community might actually have area less than 1 square mile. In these cases, the resulting population density might be greater than the actual population listed. This is not an error, but represents the results of the standard calculation.

Please visit the U.S. Census Bureau's Question and Answer Center.

• Creating Inclusive Communities in Florida, A Guidebook on Avoiding the Not In My Backyard Syndrome - A guidebook written for elected officials & their staff.
• U.S. Census Bureau Glossary of Terms