When Did NYC Lose Its Iconic Letter Telephone Exchanges?

In 1960 the New York Telephone Company declared the need to create new exchanges by using the 0 and 1 from the dial and assigned its first all-number exchange. The letters were not fully banished from the white pages until 1978. The letter exchanges denoted neighborhoods or old families or were merely made up by the telephone company supervisor John C. Doughty. 

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