Thresholds for time and income poverty in households: Evidence from joint distributions

Time poverty is a key yet conceptually contested dimension of household living standards. Both univariate and bivariate measures remain debated because there is no clear consensus on how to define and quantify socially necessary unpaid work, the time that money cannot substitute for, across household types and income levels. Existing approaches typically adjust monetary poverty lines for unpaid work responsibilities or rely on average unpaid work time, while assuming a fixed substitutability between time and money. Such measures fail to capture the joint constraints that shape household living standards. Using household-level data from the 2017 and 2019 Panel Study of Income Dynamics (PSID), the analysis supports setting 60 percent of the median as the threshold for socially necessary unpaid work in single-adult households without children and applying equivalence scales for other household types. The bivariate relative poverty line (BRPL) framework further defines nonlinear bundles of unpaid household work and food expenditure that mark the threshold for living above the poverty line. The results show that 10.1 percent of oneand two-adult households fall below the BRPL despite not being poor according to univariate measures, underscoring the importance of jointly considering time and money in assessing household living standards and poverty.