As far back as four years ago, headlines in both places trumpeted the news that the cities had traded places, Phoenix stepping up and Philadelphia falling back.
But the final hard data show different.
"It's more exciting news for the city," Mayor Nutter said Thursday night. "It's a confidence-booster. It's an image booster. . . . To be now legitimately in the top five cities in the country is putting Philadelphia in the proper spotlight."
The growth of the city and the region - surrounding suburban counties showed population increases - helps economically, politically, and psychologically, he said.
Philadelphia maintained its fifth-spot status despite the desert city's having increased in population by an impressive 9.4 percent. The growth in Philadelphia was a puny 0.6 percent, but enough to halt a 50-year trend of population loss. "The estimates of their growth were apparently overdone," deadpanned Alan Greenberger, Philadelphia's deputy mayor for economic development.
Seriously, he said, in this case, five is more than a number.
"When you have 50 years, 60 years of steady population decline, growing is a big marker. It's a big deal. I think it means something to the psychology of the city, that it's a city that has grown, and will grow."
The biggest cities in 2000 were New York, Los Angeles, Chicago, and Houston, followed by Philadelphia and Phoenix.
William Schooling, Arizona's demographer for the past two years, told the Arizona Republic that the state's own estimates were skewed by an overreliance on housing data.
He's now changing the method of computation.
The Census Bureau similarly gives weight to births and deaths, which are often reported too slowly to reflect the sudden shift that apparently occurred near the end of the decade, Schooling told the newspaper.
Back in June 2007, after three years of debate about when Phoenix would pass Philadelphia or whether it already had, the Census Bureau seemed to have settled the matter. Estimates showed that Phoenix had pushed ahead.
The estimates showed Phoenix with nearly 65,000 more people than Philadelphia as of July 1, 2006. Those estimates put Philadelphia's population at 1,448,394 - a low it has yet to reach. Phoenix was estimated at 1,512,986 - a high it has yet to hit.
Contact staff writer Jeff Gammage at 215-854-2415 or firstname.lastname@example.org.