Gini Index of Household Income Inequality
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- Definition: Difference between the estimated distribution of household income and a perfectly equal distribution, measured between 0 and 1 (e.g., in 2018, the Gini coefficient of income inequality among California households was 0.4912).
- Data Source: Population Reference Bureau, analysis of U.S. Census Bureau American Community Survey summary files and public use microdata (Dec. 2019).
- Footnote: A Gini coefficient of 0 represents perfect income equality (all households earning an equal share of income), while a coefficient of 1 represents perfect income inequality (one household earning all of the income and the rest earning none). These estimates are based on a survey of the population and are subject to both sampling and nonsampling error. The notation S refers to estimates that have been suppressed because the margin of error was 0.02 or greater. N/A means that data are not available.
Learn More About Family Income and Poverty
- Measures of Family Income and Poverty on Kidsdata.org
On kidsdata.org, family income and poverty are measured against a variety of income, resource, and self-sufficiency criteria:The U.S. Census Bureau's official poverty measure compares pre-tax cash income against a threshold of three times the cost of a minimally adequate diet in 1963, adjusted for inflation. Federal poverty thresholds aim to define and measure poverty over time, rather than describe the amount of income families need to live. The following indicators are based on the official poverty measure and come from the American Community Survey (ACS):*
- Children living in poverty (i.e., with incomes below their poverty threshold), overall and by race ethnicity
- Children living in deep poverty (i.e., with incomes below 50% of their poverty threshold)
- Children living in areas of concentrated poverty (i.e., where at least 30% of residents live in poverty)
- Income level for children as a percentage of their poverty threshold, overall and by family type
- Children living in low-income working families (i.e., with incomes below 200% of their poverty threshold and with at least one working parent)
Federal poverty guidelines are simplified federal poverty thresholds produced by the U.S. Department of Health and Human Services and used for administrative purposes such as determining eligibility for federal programs and benefits. Indicators of family income between 0-100% and 0-200% of federal poverty guidelines are provided for mothers with a recent birth. These estimates come from the Maternal and Infant Health Assessment and are available for California and its counties with the greatest number of births; in addition, state-level breakdowns by race/ethnicity and by type of prenatal health insurance coverage are provided.
The Census Bureau's Supplemental Poverty Measure (SPM) is an extension of the official poverty measure. SPM thresholds are adjusted to account for expenditures on clothing, utilities, and shelter, along with state-level differences in housing costs. To calculate family resources, the SPM adds non-cash government benefits and tax credits to cash income, and subtracts out-of-pocket work, medical, and child care expenses. National and state-level estimates of children living below their SPM poverty threshold come from the Current Population Survey and are available for children overall and by race/ethnicity.
The California Poverty Measure (CPM), a joint project of the Public Policy Institute of California and the Stanford University Center on Poverty and Inequality, incorporates California-specific threshold and resource adjustments, and allows for county-level and demographic subgroup estimates of child poverty. The following CPM indicators related to child poverty are available:
- Poverty thresholds for families with children by family composition, for renters and owners with mortgages
- Estimates of children living in poverty and deep poverty, overall and by age, race/ethnicity, family type, family citizenship status, family education level, and family employment status
- Estimates of the extent to which social safety net programs reduce child poverty and deep poverty, by program type
A project of the Center for Women's Welfare at the University of Washington, the California Family Economic Self-Sufficiency Standard measures the amount of income a family of a certain composition in a specific county needs to adequately meet its basic needs without public or private assistance. Kidsdata.org provides self-sufficiency standards for six common family types at the county level along with state- and county-level estimates of the percentage of families with children living below their standard.
In addition to these measures kidsdata.org also offers:
- Median family income (the income level at which half of families earn more and half earn less), by family type, from ACS
- Household income distribution by quintile (the percentage of aggregate household income earned by each income quintile), from ACS
- Gini index of household income inequality (a summary measure of the difference between the observed distribution of household income and a perfectly equal distribution, ranging from 0 and 1), from ACS
- The number and rate of children participating in CalWORKs (California's Temporary Assistance for Needy Families (TANF) program), from the California Department of Social Services
*Depending on the indicator, ACS data are available as single-year estimates for counties and county groups, or as five-year estimates for counties, cities and school districts of at least 10,000 residents, or legislative districts.
- Family Income and Poverty
- Children in Poverty, by Race/Ethnicity
- Children Living in Areas of Concentrated Poverty
- Children in Deep Poverty
- Median Family Income, by Family Type
- Household Income Distribution, by Quintile
- Gini Index of Household Income Inequality
- Income Level for Children Relative to Poverty
- Income Level for Children Relative to Poverty, by Family Type
- Children Living in Low-Income Working Families
- Mothers with a Recent Birth Living in Families in Poverty
- Mothers with a Recent Birth Living in Low-Income Families
- Children in Poverty - Supplemental Poverty Measure (California & U.S. Only)
- Poverty Thresholds - California Poverty Measure, by Family Composition and Housing Tenure
- Children in Poverty - California Poverty Measure
- Children in Deep Poverty - California Poverty Measure
- Poverty-Reducing Effects of the Social Safety Net - California Poverty Measure, by Program Type and Poverty Level (California Only)
- Self-Sufficiency Standard, by Family Composition
- Families Living Below Self-Sufficiency Standard
- Children Participating in CalWORKs
- Student Demographics
- Early Care and Education
- Food Security
- Childhood Adversity and Resilience
- Children with Adverse Experiences (Parent Reported), by Number (CA & U.S. Only)
- Children with Adverse Experiences (Parent Reported), by Type (CA & U.S. Only)
- Children with Two or More Adverse Experiences (Parent Reported), by Race/Ethnicity (CA & U.S. Only)
- Prevalence of Childhood Hardships (Maternal Retrospective)
- Basic Needs Not Met (Maternal Retrospective)
- Family Hunger (Maternal Retrospective)
- Moved Due to Problems Paying Rent or Mortgage (Maternal Retrospective)
- Prevalence of Adverse Childhood Experiences (Adult Retrospective; CA Only)
- Housing Affordability and Resources
- Fair Market Rent, by Unit Size
- Households with a High Housing Cost Burden
- Children Living in Crowded Households
- Children Living in Households with a Broadband-Connected Device, by Age Group
- Health Care
- Medicaid (Medi-Cal) or Children's Health Insurance Program (CHIP) Coverage
- Medicaid (Medi-Cal) or CHIP Coverage, by Age Group (California & U.S. Only)
- Medicaid (Medi-Cal) and CHIP Yearly Enrollment (California & U.S. Only)
- Medi-Cal Average Monthly Enrollment
- Medical Care Delayed or Forgone in Past Year
- Usual Source of Health Care
- Health Status
- Why This Topic Is Important
Income and well being are intricately linked. Poverty can alter children's developmental trajectories in cognitive, socio-emotional, and physical health (1). The effects of poverty on child health and well being can begin during pregnancy, as low-income women are more likely to experience malnutrition and stress, and are less likely to receive adequate prenatal care (2). Children who face economic hardship when they are young, or who experience deep and prolonged poverty, are at greatest risk for poor outcomes (1). The effects of poverty and the stress associated with it can be lasting, contributing to increased risk of dropping out of school, poor adult health, and poor employment outcomes, among other adverse consequences (1, 3, 4). The impacts extend beyond individuals, too. For example, it is estimated that the total annual cost of child poverty in the U.S. is more than a trillion dollars, due in part to loss of economic productivity and increased health care costs (5). In addition, for every dollar spent on poverty reduction strategies, the U.S. could save an estimated $7 related to the economic costs of poverty (5).The link between income and wellness is evident even for those living above the poverty threshold. A health gradient exists along the economic spectrum such that health status improves as income level increases; e.g., the health of those in the middle-income range tends to be inferior to those in higher-income groups (3). This is especially concerning given that income inequality in the U.S. has been increasing in recent decades (6).
Rates of poverty tend to be highest among children under age 5, those in single-parent families, and African American/black and Hispanic/Latino children (4, 7).
For more information on family income and poverty, see kidsdata.org’s Research & Links section.
Sources for this narrative:
1. American Academy of Pediatrics Council on Community Pediatrics. (2021). Poverty and child health in the United States. Pediatrics, 137(4), e20160339. Retrieved from: https://publications.aap.org/pediatrics/article-abstract/137/4/e20160339/81482/Poverty-and-Child-Health-in-the-United-States
2. Hamad, R., & Rehkopf, D. H. (2015). Poverty, pregnancy, and birth outcomes: A study of the Earned Income Tax Credit. Paediatric and Perinatal Epidemiology, 29(5), 444-452. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4536129
3. Aron, L., et al. (2015). Can income-related policies improve population health? Urban Institute & Virginia Commonwealth University Center on Society and Health. Retrieved from: https://www.urban.org/research/publication/can-income-related-policies-improve-population-health
4. Murphey, D., & Redd, Z. (2014). Five ways poverty harms children. Child Trends. Retrieved from: https://www.childtrends.org/publications/5-ways-poverty-harms-children
5. McLaughlin, M., & Rank, M. R. (2018). Estimating the economic cost of childhood poverty in the United States. Social Work Research, 42(2), 73-83. Retrieved from: https://academic.oup.com/swr/article-abstract/42/2/73/4956930
6. Stone, C., et al. (2020). A guide to statistics on historical trends in income inequality. Center on Budget and Policy Priorities. Retrieved from: https://www.cbpp.org/research/poverty-and-inequality/a-guide-to-statistics-on-historical-trends-in-income-inequality
7. Bohn, S., & Danielson, C. (2017). Geography of child poverty in California. Public Policy Institute of California. Retrieved from: https://www.ppic.org/publication/geography-of-child-poverty-in-california
- How Children Are Faring
In 2018, an estimated 17% of California children lived below the federal poverty threshold ($25,465 annually for a family of two adults and two children). Across counties with data in 2018, official child poverty rates ranged from less than 4% in Marin County to more than 30% in Fresno County. In Merced and Tulare counties in 2018, more than one in eight children lived in deep poverty—i.e., on annual income lower than half the federal poverty threshold ($12,732 for two adults and two children in 2018).
The Supplemental Poverty Measure (SPM) accounts for expenses (e.g., state-level differences in housing costs) and resources (e.g., government safety net program benefits) not captured in the official poverty measure. According to SPM estimates, 13% of California children lived in poverty in 2020. California's SPM child poverty rate consistently exceeds comparable U.S. figures. More than one in five African American/black and Hispanic/Latino children in California lived below their SPM threshold in 2018-2020, compared with fewer than one in twelve of their white and multiracial peers.
The California Poverty Measure (CPM) builds on the SPM by adjusting for California-specific safety net policies and for regional variation in the cost of living within the state. CPM data from 2017-2019 show that 19% of children statewide lived in poverty and 4% lived in deep poverty. In the absence of social safety net programs, it is estimated that the child poverty rate would have been 13 percentage points higher and the deep poverty rate 10 percentage points higher during this period. CPM child poverty rates vary widely across counties, from 10% in Placer County to 24% in Orange County, among regions with data in 2017-2019. Overall, children whose parents are single, non-U.S. citizens, or who did not finish high school tend to experience higher rates of CPM poverty and deep poverty than children in families with married parents, U.S. citizens, and higher levels of educational attainment.
The Self-Sufficiency Standard (SSS) represents the estimated income a family needs to adequately meet its basic needs without public or private assistance. Across California counties, the SSS for a family of two adults and two school-aged children in 2018 ranged from $52,566 (Modoc) to $114,215 (Marin) annually. In 2016, nearly half (48%) of all families with children statewide lived on incomes below their SSS.Rates of poverty among California women with a recent birth—and, by extension, their children—are especially high. Statewide, an estimated 41% of mothers with a birth in 2013-2014 lived in families with income below the federal poverty guideline ($23,850 for a family of four in 2014); for African American/black and Hispanic/Latina mothers, the poverty rate was 60%, compared with 20% or less for Asian/Pacific Islander and white mothers.
Income is not distributed evenly across California households and regions. Statewide and nationally, when households are divided by income into five equally sized groups, those in the highest quintile earned an estimated 52% of all household income in 2018, compared with a 3% share of total income earned by households in the lowest quintile. Among counties with data, median annual income for families with children ranged from $43,287 in Lake County to $167,766 in Marin County in 2014-2018. Marin County also had the highest level of household income inequality among counties with data in 2014-2018, as measured by the Gini index.
The CalWORKs program, which provides cash aid and services to needy families, served more than 720,000 California children—a rate of 80 per 1,000—in 2020. Among counties with data, participation in CalWORKs ranged from 9 per 1,000 children in San Mateo County to 184 per 1,000 in Del Norte County.
- Policy Implications
Poverty has multiple causes and dimensions, many of which public policy can address. Maintaining a public safety net for pregnant women and families lacking adequate resources for food, clothing, health care, and shelter can mitigate economic hardship (1, 2). Other strategies, such as tax credits and parental work support, also help families meet their basic needs. Reducing child poverty, and income inequality more broadly, requires a long-term commitment from leaders at the local, state, and federal levels, as well as a broad policy strategy targeting poverty's diverse root causes. While California has made strides in recent years, including a new state Earned Income Tax Credit and minimum wage increases, continued efforts are needed to ensure that all children and families have the opportunity to thrive (1).
Policy and program options that could influence family income and poverty include:
For more policy ideas and information on this topic see kidsdata.org’s Research & Links section or visit Public Policy Institute of California, California Budget and Policy Center, and Center for Law and Social Policy. Also see Policy Implications on kidsdata.org under Food Security, Housing Affordability and Resources, Health Care, and Early Care and Education.
- Maintaining and strengthening CalWORKs (California's version of the federal Temporary Assistance to Needy Families (TANF) program, which provides cash assistance and employment support to families), ensuring that benefits support an adequate living standard and families receive the assistance necessary to transition from welfare to work (1, 3, 4)
- Ensuring that eligible families enroll in safety net programs—e.g., CalFresh (California's version of the federal Supplemental Nutrition Assistance Program (SNAP), also known as food stamps), the Supplemental Nutrition Program for Women, Infants, and Children (WIC), and free or reduced-price school meals—through outreach and elimination of administrative barriers; also, ensuring that safety net programs have the capacity to expand during economic downturns, when unemployment and family needs increase (1, 4, 5)
- Maintaining and strengthening tax credits aimed at reducing poverty among families, e.g., the federal Earned Income Tax Credit and Child Tax Credit, and raising awareness about the California Earned Income Tax Credit (1, 6, 7)
- Extending refundable state tax credits to all families with children, irrespective of immigration status, and including those with no earned income (7)
- Increasing access to high-quality, affordable child care in a variety of settings, especially for low-income children, by capitalizing on the expansion of federal and state subsidies for early childhood programs and ensuring that eligible children receive subsidies (8)
- Strengthening and increasing participation in California's Paid Family Leave program by raising the rate of earnings replacement and providing job protection for those who take time away from work to care for or bond with a new child (9)
- Promoting state and local policies to increase the supply of affordable housing, such as expanding housing bonds, supporting inclusionary zoning requirements, and creating other funding mechanisms (10)
- Adjusting state tax credits to account for regional variation in the cost of living, and expanding eligibility for safety net programs in particularly high-cost areas (7, 11)
- Ensuring comprehensive and consistent benefits across public and private health insurance carriers, so that all families can access high-quality, affordable care; this may include increasing Medi-Cal provider rates, reducing the administrative burden on providers, and developing a tool to regularly monitor children's access to quality care in Medi-Cal (8)
- Continuing to strengthen child support enforcement programs that work effectively with non-custodial parents and ensure that support reaches the families that need it (12)
Sources for this narrative:
1. Danielson, C., et al. (2021). California's future: Safety net. Public Policy Institute of California. Retrieved from: https://www.ppic.org/publication/californias-future-safety-net
2. Page, M. (2017). Safety net programs have long-term benefits for children in poor households. UC Davis Center for Poverty Research. Retrieved from: https://poverty.ucdavis.edu/policy-brief/safety-net-programs-have-long-term-benefits-children-poor-households
3. Davis, L. M., et al. (2016). Evaluation of the SB 1041 reforms to California's CalWORKs welfare-to-work program: Findings regarding the initial policy implementation and outcomes. RAND Corporation. Retrieved from: https://www.rand.org/pubs/research_reports/RR1348.html
4. Schumacher, K. (2015). Even CalWORKs and CalFresh food assistance combined fails to lift families out of poverty. California Budget and Policy Center. Retrieved from: https://calbudgetcenter.org/resources/even-calworks-and-calfresh-food-assistance-combined-fails-to-lift-families-out-of-poverty
5. California Department of Public Health, Center for Family Health. (2016). Making connections: Understanding women's reasons for not enrolling in WIC during pregnancy, California 2010-2012. Retrieved from: https://www.cdph.ca.gov/Programs/CFH/DMCAH/MIHA/CDPH Document Library/MIHA-MakingConnections-2010-2012.pdf
6. Anderson, A. (2017). More awareness should be raised on the California Earned Income Tax Credit. California Budget and Policy Center. Retrieved from: https://calbudgetcenter.org/resources/more-awareness-should-be-raised-on-the-california-earned-income-tax-credit
7. Bohn, S, & Danielson, C. (2017). Reducing child poverty in California: A look at housing costs, wages, and the safety net. Public Policy Institute of California. Retrieved from: https://www.ppic.org/publication/reducing-child-poverty-in-california-a-look-at-housing-costs-wages-and-the-safety-net
8. Children Now. (2020). 2020 California children's report card: A survey of kids' well-being and roadmap for the future. Retrieved from: https://www.childrennow.org/portfolio-posts/20-report-card
9. Stanczyk, A. B. (2016). Paid family leave may reduce poverty following a birth: Evidence from California. Employment Instability, Family Well-Being, and Social Policy Network. Retrieved from: https://cpb-us-w2.wpmucdn.com/voices.uchicago.edu/dist/5/1068/files/2018/05/stanczyk_einetbrief-13l9z7e.pdf
10. Johnson, H., et al. (2020). California's future: Housing. Public Policy Institute of California. Retrieved from: https://www.ppic.org/publication/californias-future-housing
11. Bohn, S., & Danielson, C. (2017). Geography of child poverty in California. Public Policy Institute of California. Retrieved from: https://www.ppic.org/publication/geography-of-child-poverty-in-california
12. U.S. Department of Health and Human Services, Administration for Children and Families. (2021). Office of Child Support Enforcement annual report to Congress FY 2018. Retrieved from: https://www.acf.hhs.gov/css/report/fy-2018-annual-report-congress
- Research & Links
- Websites with Related Information
- California Budget and Policy Center
- Center for Law and Social Policy (CLASP): Income and Work Supports
- Center for the Study of Social Policy: Addressing Poverty
- Center on Budget and Policy Priorities
- Child Trends: Poverty and Inequality
- First Focus on Children: Poverty and Family Economics
- Institute for Women's Policy Research
- MDRC: Work and Income Security
- National Center for Children in Poverty. Bank Street Graduate School of Education.
- Opportunity Insights
- Pew Charitable Trusts: Finance and Economy
- Public Policy Institute of California
- Spotlight on Poverty and Opportunity
- Stanford Center on Poverty and Inequality
- Supplemental Poverty Measure. U.S. Census Bureau.
- U.S. Partnership on Mobility from Poverty. Urban Institute.
- Urban Institute: Poverty
- Key Reports and Research
- A Guide to Understanding Poverty Measures Used to Assess Economic Well-Being in California. (2019). California Budget and Policy Center. Anderson, A., & Kimberlin, S.
- A Roadmap to Reducing Child Poverty. (2019). National Academies Press. National Academies of Sciences, Engineering, and Medicine.
- An Update on the Portrait of Promise: Demographic Report on Health and Mental Health Equity in California. (2020). California Dept. of Public Health, Office of Health Equity.
- Basic Facts About Low-Income Children: Children Under 18 Years, 2019. (2021). National Center for Children in Poverty. Koball, H., et al.
- California's Future: Safety Net. (2021). Public Policy Institute of California. Danielson, C. et al.
- Child Poverty in the United States. (2016). Academic Pediatrics. Dreyer, B., et al. (Eds.)
- Escaping Poverty: Predictors of Persistently Poor Children’s Economic Success. (2017). U.S. Partnership on Mobility from Poverty. Ratcliffe, C., & Kalish, E.
- Five Ways Neighborhoods of Concentrated Disadvantage Harm Children. (2018). Child Trends. Sacks, V.
- Geography of Child Poverty in California. (2017). Public Policy Institute of California. Bohn, S., & Danielson, C.
- Making Ends Meet: How Much Does It Cost to Support a Family in California? (2017). California Budget and Policy Center. Kimberlin, S., & Rose, A.
- Our Kids, Our Future: Solutions to Child Poverty in the U.S. (2018). U.S. Child Poverty Action Group.
- Poverty and Child Health in the United States. (2021). Pediatrics. American Academy of Pediatrics Council on Community Pediatrics.
- Race and Economic Opportunity in the United States: An Intergenerational Perspective. (2019). National Bureau of Economic Research. Chetty, R., et al.
- Recommended Strategies to Address Deep Child Poverty and Child Poverty in California. (2018). Lifting Children and Families Out of Poverty Task Force.
- Reducing Child Poverty in California: A Look at Housing Costs, Wages, and the Safety Net. (2017). Public Policy Institute of California. Bohn, S., & Danielson, C.
- Struggling to Move Up: The Real Cost Measure in California 2021. United Ways of California. Manzo, P., et al.
- The Cost of Being Californian: 2021. (2021). Insight Center for Community Economic Development. Price, A., & Villarosa, A.
- The Ethical and Policy Implications of Research on Income Inequality and Child Well-Being. (2015). Pediatrics. Pickett, K. E., & Wilkinson, R. G.
- Turning One Year of Age in a Low Socioeconomic Environment: A Portrait of Disadvantage. (2017). Journal of Developmental and Behavioral Pediatrics. Hunt, H., & Betancourt, L. M.
- What Explains the Widespread Material Hardship Among Low-Income Families with Children? (2018). Urban Institute. Karpman, M., et al.
- County/Regional Reports
- A Portrait of Los Angeles County: Los Angeles County Human Development Report 2017-2018. (2018). Measure of America. Lewis, K., & Burd-Sharps, S.
- A Portrait of Sonoma County. (2022). Measure of America. Lewis, K., et al.
- Annual Report on the Conditions of Children in Orange County. Orange County Children's Partnership.
- Community Health Improvement Plan for Los Angeles County. Los Angeles County Dept. of Public Health.
- Important Facts About Kern’s Children. Kern County Network for Children.
- Inequality and Economic Security in Silicon Valley. (2016). California Budget and Policy Center. Reidenbach, L., et al.
- Live Well San Diego Report Card on Children, Families, and Community. The Children’s Initiative.
- Orange County Community Indicators Report. Orange County Business Council, et al.
- Pathway to Progress: Indicators of Young Child Well-Being in Los Angeles County. First 5 LA.
- San Mateo County All Together Better. San Mateo County Health.
- Santa Clara County Children's Data Book. Santa Clara County Office of Education, et al.
- Santa Clara County Public Health Department: Open Data Portal
- Santa Monica Youth Wellbeing Report Card. Santa Monica Cradle to Career.
- Spotlight on the Inland Empire. (2021). Measure of America. Lewis, K.
- The Color of Wealth in Los Angeles. (2016). Duke University, et al. De La Cruz-Viesca, M., et al.
- Youth Need Data. Get Healthy San Mateo County.
- More Data Sources For Family Income and Poverty
- 2022 KIDS COUNT Data Book: State Trends in Child Well-Being. Annie E. Casey Foundation.
- California Family Needs Calculator. Insight Center for Community Economic Development.
- California Health and Human Services Open Data Portal. California Health and Human Services Agency.
- California Health Interview Survey. UCLA Center for Health Policy Research.
- Community Commons: Community Health Needs Assessments
- Geography of Child Poverty in California: Interactive Map. Public Policy Institute of California.
- Health, United States – Data Finder. National Center for Health Statistics.
- Maternal and Infant Health Assessment (MIHA). California Dept. of Public Health & University of California San Francisco.
- The Well-Being and Basic Needs Survey. Urban Institute.
- U.S. Census Bureau: Poverty
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