Children under age 18 living in the household, headed by a female without a husband present. "Own children" includes never-married persons under age 18 who are the sons or daughters of the heads of the household. The heads' stepchildren and adopted children are also counted as "own children."
Data for this measure come from the U.S. Census Bureau's American Fact Finder, 2005-2007, 2006-2008, 2007-2009 and 2008-2010 American Community Survey (ACS) 3-Year Estimates.
The 2008-2010 ACS data release marked the fourth time that 3-year estimates were released for areas with populations of 20,000 and greater. The ACS 2008-2010 data were collected during calendar years 2008, 2009, and 2010. The ACS 2007-2009 data were collected during calendar years 2007, 2008, and 2009. The ACS 2006-2008 data were collected during calendar years 2006, 2007, and 2008. The ACS 2005-2007 data were collected during calendar years 2005, 2006 and 2007.
The 3-year ACS estimates represent the average characteristics over the 3-year period of time, and therefore are less current than 1-year ACS estimates. However, these estimates are more reliable because they are based on a larger sample size. The 3-year estimates are also available for more geographic areas because they are published for populations of 20,000 or greater, while 1-year estimates are only published for populations of 65,000 or greater. More information about 1-year versus 3-year ACS surveys and estimates are available online at http://www.census.gov/acs/www/data_documentation/documentation_main/.
Note: Maps use the natural break classification method, which reflects patterns
in the data by dividing the map into naturally occurring groups. Using statistical tools, this method
determines cut-off points for each group by identifying large gaps in data values.