When the latest census figures came out Wednesday, they contained a mystery for Raleigh: Where did 10,000 people go?
The U.S. Census Bureau put Raleigh's population at 276,093, a 33 percent increase over 10 years. But Cindy Szwarckop, Raleigh's demographer, had estimated the city's population at nearly 287,000 last summer.
Szwarckop thinks she knows why the two numbers are so far apart. Part of the answer, she said, may lie in census tract 051100 on the city's west side.
According to the Census Bureau, only 1,388 people live in the tract, which includes most of N.C. State University's main campus and some of the student-laden neighborhoods surrounding it. But that would be a 74.4 percent drop since 1990. Not even the state's smallest towns shrank that much.
"Obviously, there's a big undercount right there," Szwarckop said. "There's a lot of students that live in that tract that they did not count."
Raleigh has been through this before. In 1990, the city complained that the Census Bureau missed about 3,000 students. Eventually, the bureau corrected Wake County's population by about that much, though it never acknowledged where the undercount took place.
But why the count in tract 051100 should be so far below even the disputed 1990 figure is a mystery.
"It sounds like what happened is a procedural problem," said Bob Coats, an analyst with the State Data Center. "But I can't say that's what it was."
University students are always difficult to count, but students who live off campus are the worst, said Susan Hardy, director of the Census Bureau regional office in Charlotte.
Universities help count students in dormitories, but students off campus often share apartments or houses in which no one takes responsibility for filling out the census forms. Follow-up surveys happen in the spring, when students are leaving town.
The Wake County Complete Count Committee, a group created to encourage people to fill out their census forms, targeted students at NCSU and Raleigh's other colleges and universities, with campus rallies and mass mailings.
Still, less than 19 percent of the census forms from tract 051100 were returned, by far the lowest rate of any tract in the county, said Maja Vouk, the county demographer.
"It has a category by itself because it was so low," Vouk said. "We could not pinpoint why we couldn't get the forms back."
NCSU students may not be the only undercounted collegians in the Triangle.
The population of the census tract that includes Duke University's West Campus in Durham shrank by 35 percent in the 1990s. Duke spokesman Al Rossiter said there haven't been any changes that would explain a decline, let alone one that large.
By contrast, population in the census tracts around N.C. Central University in Durham declined only slightly, and they increased for the University of North Carolina and environs in Chapel Hill.
Szwarckop says she'll also make sure the Census Bureau didn't leave out some areas that Raleigh annexed just before the April census. In the end, if city officials believe the agency erred, they can appeal the count, as they did in 1990.
Szwarckop says it's possible her estimate was high, but not by much.
"It's a guessing game when you do estimates and projections," she said.
Staff writer Richard Stradling can be reached at 829-4739 or firstname.lastname@example.org