WASHINGTON - The time when aging baby boomers will place an overwhelming demand on the United States' long-term care system might be more than two decades away, a report released yesterday said.

Improved socioeconomic conditions and higher education levels among the baby boom generation have contributed to a decrease in disability rates, according to the report by AARP, the nation's largest lobbying group for older people.

Previous studies had predicted a substantial increase in demand for long-term support services as the 76 million Americans born between 1946 and 1964 reach the ages of 75 to 80. The oldest baby boomers will reach age 75 in 2021.

According to the new study, the number of elderly with disabilities and those in nursing homes has declined slightly over the past 10 to 15 years, despite an aging population.

About 1.8 million disabled elderly Americans were living in nursing homes in 1994, according to Duke University's Center for Demographic Studies.