On intra-annual consumption-poverty in the U.S: Response to SNAP and the importance of within-year variation

•CES data show 10% of U.S. households consume sub-poverty resources at least one quarter per year.•Nearly half of the intra-annually poor (IAP) are not classified as poor by annual statistics.•IAP families are more likely to join SNAP than non-poor, but less than annually poor families.•SNAP participation reduces intra-annual and annual poverty.

We use U.S. quarterly consumption data and decomposable poverty indexes to study consumption-based intra-annual poverty and its relationship to participation in the Supplemental Nutrition Assistance Program (SNAP). Intra-annual spells of consumption-poverty account for half of the incidence and one-third of the severity of all consumption-poverty among U.S. households. Households experiencing consumption-poverty for at least one quarter, but not for the whole year, are more likely to self-select into SNAP than the general population but less likely to do so than those who are poor for the year. SNAP participation, in turn, reduces annual and intra-annual poverty.