DETROIT (AP) — Secretary of State Ruth Johnson has announced that 52 percent of Michigan adults are registered as organ donors.

Johnson says Saturday in Detroit that the Michigan Organ Donor Registry now stands at more than four million people.

Two million people have added their names to the registry over the past four years. About 85 percent of those who register sign up through the Secretary of State’s office.

Johnson said about 3,500 Michigan residents are awaiting organ transplants. She told participants at the 18th annual LIFE Walk on Belle Isle that “organ, tissue and eye donation saves and improves lives.”

The event is sponsored by Gift of Life Michigan’s Minority Organ, Tissue Transplant Education Program which works to reduce the need for organ and tissue transplants among ethnic and minority populations.