Families are considered to be living in poverty if their pre-tax income (not including in-kind benefits such as SNAP benefits [food stamps] or the Earned Income Tax Credit) is less than the federal poverty level (FPL), an income threshold that varies by family size and composition. The thresholds are updated annually to reflect inflation as measured by the Consumer Price Index (CPI). In 2017 the poverty threshold for a family of four with two related children under age 18 was $25,094, while the threshold for a family of three with two related children was $19,515. The thresholds are determined by estimating the cost of a minimally adequate diet for a family of a given configuration and size, multiplied by three.
Poverty thresholds for 1959 and beyond for various family configurations are available at http://www.census.gov/data/tables/time-series/demo/income-poverty/historical-poverty-people.html (Table 1).
Because the survey asks about income in the previous year, data for each year were collected in March of the following year. For instance, data on 2017 poverty were collected in March 2018.
In 2014, questions related to income were changed slightly, and this reduced comparability with previous data. More detail on this change is available at https://www.census.gov/content/dam/Census/library/working-papers/2015/DEMO/ASSA-Income-CPSASEC-Red.pdf.
 DeNavas-Walt, C. & Proctor, B. D. (2014). Income and poverty in the United States: 2013. Current Population Reports, Series P60-249. Retrieved from http://www.census.gov/content/dam/Census/library/publications/2014/demo/p60-249.pdf.
 For discussion of the limitations of the federal poverty measure, see Blank, R. M. & Greenberg, M. H. (2008). Improving the measurement of poverty (Discussion Paper 2008-17). Washington, DC: The Brookings Institution. Retrieved from http://www.brookings.edu/research/papers/2008/12/poverty-measurement-blank.
 Fox, L. (2018). The Supplemental Poverty Measure: 2017. Current Population Reports, Series P60-265, Table A-6. Retrieved from https://www.census.gov/content/dam/Census/library/publications/2018/demo/p60-265.pdf.
 Hispanics may be any race. Estimates for whites in this report do not include Hispanics.
Child Trends Databank. (2019). Children in poverty. Available at: https://www.childtrends.org/?indicators=children-in-poverty