Background and Objectives: We examine trends in informal care from the perspective of both community-dwelling disabled older Americans and their caregivers from 1982 to 2012. We decompose hours of care received from spouses and children according to changes in: (a) the number of potential spousal and child caregivers ("family structure"), (b) the likelihood that existing spouses and children are caregivers ("caregiving propensity"), and (c) the amount of care provided by individual caregivers ("time burden").; Research Design and Methods: We examine two sets of time trends based on distinct samples of community-dwelling disabled older Americans from the 1982-2004 waves of the National Long-Term Care Survey (NLTCS) and the 2000-2012 waves of the Health and Retirement Study (HRS).; Results: Existing spouses' and children's decreasing likelihood of being caregivers led to fewer spousal and child caregivers per disabled older person in the 2004 NLTCS than the 1982 NLTCS. However, the NLTCS and HRS time trends suggest that the amount of care provided by individual caregivers was similar from 1989 to 2012.; Discussion and Implications: Because individual caregivers' time burden has remained fairly constant since at least 1989, advocacy on behalf of policies that promote more and better support for caregivers is appropriate.