NEW YORK – The Postal Service, which mapped out social class four decades ago by separating people into ZIP codes, is about to give a new dimension to the adage “there goes the neighborhood.” This summer, ZIP code 10021 on the Upper East Side will become even more exclusive. About 50,000 Manhattanites, including Mayor Michael R. Bloomberg, David Rockefeller, Rupert Murdoch, Ronald Perelman, Spike Lee, Tom Wolfe and Gay Talese, will be cast out from the ranks of 10021 residents. They will be relegated instead to one of two new ZIP codes, either 10065 (60th to 69th Streets, from Fifth Avenue to the East River) or 10075 (East 76th Street to East 80th). 160Want local news?Sign up for the Localist and stay informed Something went wrong. Please try again.subscribeCongratulations! You’re all set!