In 1993, researchers collaborated with the Group Health Cooperative of Puget Sound and Senior Services of Seattle/King County to develop a physical activity program for adults aged 60 years or older. The program emphasizes activities to increase endurance, strength, balance, and flexibility. The pilot study showed that participants improved significantly in almost every area tested—from physical and social functioning to levels of pain and depression. The health care costs for participants attending at least once a week have been significantly reduced. Now the program is offered at 315 community sites in 26 states, and the researchers continue to evaluate and refine the program. In 2003, the National Council on Aging selected the physical activity program as one of the top ten in the United States.