Central started business in Ann Arbor in 1963. As of December 31, 1966, Central owned 60 billboards at 28 locations within the City of Ann Arbor, 58 of which existed at time of trial. All but 2 are of 300 square feet, a size which has been adopted in the more than 1,000 member industry so that standardized posters can be used. The other 2 are a standard 750 square feet. All have been declared nonconforming as a result of the sign ordinance. Central complains that it stands to lose its entire Ann Arbor market investment valued in excess of $300,000. Central also will lose substantial fees derived from servicing signs owned by others, including the other plaintiffs.