How much of the US population is eligible to donate blood?

Estimates by the American Red Cross and America's Blood Centers suggest that less than 5% of eligible blood donors provide all the volunteer blood components each year. Approximately 14-16 million donations are made each year, by 8-9 million donors, producing 30-45 million transfusable blood components.

AABB.org

FDA.gov

Americasblood.org