Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!swbatl!texbell!vector!telecom-gateway From: vern@zebra.uucp Newsgroups: comp.dcom.telecom Subject: Re: NPA Splits Before 1965 Message-ID: Date: 6 Oct 89 13:52:29 GMT Sender: news@vector.Dallas.TX.US Lines: 33 Approved: telecom-request@vector.dallas.tx.us X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@vector.dallas.tx.us X-TELECOM-Digest: volume 9, issue 433, message 3 of 5 In article , covert@covert.enet.dec. com (Greg Monti) writes: > I thought that, when Area Codes were 'invented' in 1946 (not 'implemented,' > just 'invented'), the system was as follows: > - States small enough to require only one area code got a zero as the center > digit, with the other digits depending on population density or urbanization > (higher numbers to more rural states). The most urban, New Jersey, got the > lowest number of this series, 201. DC got 202. > - States big enough to require more than one area code at the outset got all > codes with a 1 as the center digit. The outer digits were assigned in the > same general way as described above. New York got 212, the second and third > most populous cities got 213 and 312, other big cities got 214, 412, 215, > etc. My father was Dial Traffic Engineer here in Denver when DDD was first announced. He explained that areas codes were assigned on the basis of incoming long distance traffic to the area. The areas having the most traffic at the time were New York City ( 212 ) and Los Angeles ( 213 ) even though they were a continent apart. These numbers were selected because they were the easiest to dial on a rotary dial. I'm not sure where the break point was in deciding whether a center digit of zero was easier to dial than one with larger end digits and a one in the center. Obviously 202 was easier that 919. Maybe just add up the digits and you get a list with N1N and N0N's scrambled in the mid region? Vernon C. Hoxie {ncar,nbires,boulder,isis}!scicom!zebra!vern 3975 W. 29th Ave. voice: 303-477-1780 Denver, Colo., 80212 TB+ uucp: 303-455-2670