The percentage of registered nurses working in long-term care has barely budged over the last five years, according to preliminary results of a national study. About 6.3% of all RNs reported nursing homes or extended care facilities as their primary place of employment, according to the 2004 National Sample Survey of Registered Nurses.

Ambulatory care settings saw the largest percentage increase (to 11.5% from 9.5%) from 2000 to 2004. This category includes places such as physician-based practices, nurse-based practices and health maintenance organizations. Although the estimated number of RNs in hospitals increased, their percentage dropped, to 56.2% from 59.1%. Authors said the shift might reflect structural changes in hospitals, such as more specialty outpatient clinics.

The survey also found that nurses are getting older. The average age rose to 46.8 years from 45.2 years in 2000. Also in 2000, nearly a third (31.7%) of all RNs were under age 40; that figure has dropped even further (to 26.6%), according to the study.

Overall, the number of RNs in the U.S. has risen 7.9% (to 2.9 million) since 2000. About 78% of nurses said they were satisfied with their jobs. Only 13.8% were dissatisfied. The Health Resources and Services Administration’s Bureau of Health Professions conducts the survey every four years, and expects to publish complete results next month.