Daily Effective Circulation (DEC): The average number of daily potential exposures to a display or group of signs. DEC is determined by counting only those vehicles traveling toward the face of the sign and then multiplying that number by the average number of people per car during the hours the sign is visible. Pedestrian and mass-transit circulations are not included. This is the basic measure in establishing cost-per-thousand exposures on signs. The basic traffic numbers can usually be obtained from state departments of transportation.
Dimensional Letter: A cut-out, cast, fabricated, or molded material such as metal or plastic, in the shape of a letter, logo, or symbol.Directory Sign: A sign that identifies the names and locations of tenants in a multi-tenant building or in a development made up of a group of buildings.
