NOTE: Estimates of “living with a partner” include changes in measurement over time. From 1967 to 1995, estimates of unmarried couples use an indirect measure, POSSLQ (partners of the opposite sex sharing living quarters). From 1996 to 2006 'unmarried partner' was an answer category on the relationship to householder question, so estimates are restricted to adults where one of the partners is the householder. Since 2007, when a direct question asking about the presence of unmarried partners was added to the survey, all cohabiting partners are included regardless of whether they are the householder.

NOTE: Estimates of “living with a partner” include changes in measurement over time. From 1967 to 1995, estimates of unmarried couples use an indirect measure, POSSLQ (partners of the opposite sex sharing living quarters). From 1996 to 2006 'unmarried partner' was an answer category on the relationship to householder question, so estimates are restricted to adults where one of the partners is the householder. Since 2007, when a direct question asking about the presence of unmarried partners was added to the survey, all cohabiting partners are included regardless of whether they are the householder.