John Albin is a retired partner of Brill & Crum, a personal service partnership. Albin has not rendered any services to Brill & Crum since his retirement over 10 years ago. Under the provisions of Albin's retirement agreement, Brill & Crum is obligated to pay Albin 10% of the partnership's net income each year. In compliance with this agreement, Brill & Crum paid Albin $25,000 this year. How should Albin treat this $25,000?