D.C.

Headquartered in Washington, D.C., the United States Postal Service’s (USPS) 4-state customer bar code greatly increases the amount of information carried within a bar code, yet uses less space, providing greater data capacity. The new bar code integrates the delivery information of the zip-plus-four and delivery point with a detailed tracking number in a single, height-modulated bar code featuring four distinct vertical bar types—full, tracker, ascender and descender. The 31-digit 4-state customer bar code (65 bars) is slightly longer than the 11-digit POSTNET (62 bars), and offers mailers certain flexibility in choosing the height and width of the bar code. Effective Sept. 2006, mailers