The analysts at P.H.I., a nonprofit research and consulting group, sift through federal data each year to see how the nation’s swelling corps of home care workers is faring.

That’s how we know that the aides who care for disabled people and older adults in their homes — helping them bathe and dress, preparing their meals, doing laundry and housekeeping — earned a national median of $10.21 an hour in 2005, adjusted for inflation.

P.H.I. published its most recent findings this month, so we also know that a decade later, home care aides earn even less: $10.11 an hour.

This helps explain why Patricia Walker, 55, a certified nursing assistant who works for a home care agency in Tampa, Fla., and provides care for two older men — and hasn’t received a raise in five years — must rely on $194 in food stamps each month.