We suggest two supplements to Franco Modigliani's lifecycle model in order to explain why people who have retired from paid work choose either to start volunteering or increase the amount of time they devote to volunteer work. First, total consumption consists of both the material and immaterial products of work. While people can save their income in order to maintain an even level of material consumption, they unable to save a portion of the immaterial product. Second, at the statutory retirement age people retire only from paid work. We argue that older people substitute paid work for volunteering due to their inherent need to maintain immaterial consumption during retirement.
