Thursday, Sept. 13, 2007 | 7:38 a.m.
It may be the most bandied about factoid you'll ever hear about Las Vegas. Seven thousand people move here every month. (Or 5,000 or 6,500, depending on the time of year.)
People cite it at cocktail parties, marketing seminars and on Capitol Hill, usually to provoke a reaction or stir business juices. Yeah, that's how fast Southern Nevada is growing. Seven thousand a month!
Most people don't know where the number comes from, or bother to ask. It's simply accepted as fact. Must be, because everyone talks about it.
So you might think a number this important must have been painstakingly extrapolated by supercomputers crunching the latest statistical trends.
Meet Peggy Jackman.
She's a researcher at UNLV who, since 1991, has been sitting down two days a month at a small desk in a Department of Motor Vehicles warehouse on West Tropicana Avenue, counting the driver's licenses that motorists surrender when they move to Nevada and get a new license.
She tallies the number of licenses by state, by age, by sex. She is the dame of driver's license demographics. She is the lady behind the number.
"When I hear someone quote the statistic on the radio or TV I say, 'Hey I know where they got that from,' " said Jackman, 43, who has an education degree from UNLV. "So, yes, doing the count is a source of pride."
The number comes with a big asterisk. The figure reflects licensed drivers who give up one license to get a Nevada one. It does not reflect nondrivers, including children. So Jackman's number is not the last word on Nevada's growth.
But it's certainly the most current, and pretty darned accurate at that.
Gathering the DMV numbers was the brainchild of Keith Schwer, director of UNLV's Center for Business and Economic Research.
Schwer says using the DMV count was an easy and cheap way to satisfy the needs of a long-forgotten client who was trying to gauge Las Vegas' tremendous growth in 1986 to determine whether the city needed more apartments.
The data proved fascinating, Schwer said.
"You've got a lot of people out there trying to monitor the growth rate, and our method offers a simplistic solution. It's only one indicator - and maybe not the best - but it has worked for large numbers of people over the years."
Since 1991 the tedious monthly number-counting duty has fallen to Jackman, who works in Schwer's office. Monthly, she sends out the latest figures to a list of interested people, including politicians, chambers of commerce and bureaucrats.
Jon Summers, spokesman for Senate Majority Leader Harry Reid, D-Nev., says his office uses a combination of the U.S. census and UNLV's license count numbers when discussing growth issues as they pertain to potential legislation.
"Although the UNLV count is not a perfect method , it has proved to be a reliable source," Summers said. "It helps a lot on issues of infrastructure."
Schwer is the first to admit his counting system has its share of flaws, including that it doesn't measure the number of people who move away, are born here or die.
"Our count is only meant to be a dashboard indicator," Schwer said.
But it's valuable when considering how difficult it is to get good, up-to-date statistics on Clark County's population. Even the best local population estimates differ by more than 100,000 people, based on relatively old data.
The Nevada demographer's office says the county has 1,874,837 residents based on its latest available statistics - from July 2006.
Clark County's Advanced Planning Division, which also keeps population numbers to address infrastructure and other growth issues, says the county has 1,912,654 residents, also as of July 2006.
The census is taken every 10 years, although that federal agency makes annual population projection updates. The latest one says Clark County has 1,777,539 residents based on data from - you guessed it - 2006.
Why are the most currently available numbers 12 to 14 months old? The groups that do the counting say statistics take time to compile. But, take heart . They say the numbers for July are being crunched right now and should be out soon - by January 2008, they reckon.
Nevada State Demographer Jeff Hardcastle said he is hesitant to give even an educated guess on what Clark County's population is because past projections have been off the mark. He would not even go out on a seemingly sturdy limb to say Clark County already has reached the 2 million person mark, although given past annual growth spurts, it probably has.
The demographer's population counts are far more scientific than that of the simple UNLV license count formula.
The state factors in the actual number of housing units, the occupancy rate as determined from the annual postal vacancy survey, persons per household from the 2000 Census, workforce jobs, the unemployment rate, school enrollment, births and deaths , and other factors.
Still, Hardcastle says , the UNLV license count survey is good for producing ballpark growth numbers.
And, over the years, he said, UNLV's numbers have in the final analysis come pretty close to the actual net growth.
By comparison, the demographer's office found that from 2005 to 2006, there was a net increase of 6,538 Clark County residents per month, while UNLV's license count for 2006 showed an increase of 6,781 Clark County residents per month.
And UNLV needed only Jackman to come up with those figures.
The UNLV survey also shows there has been a steady decrease in the growth rate since 2003, when on average 7,491 new residents flooded Clark County monthly.
The UNLV license counts also have been remarkably consistent over the years. Every month, at least a third of the turned-in licenses come from California. And more than half of the surrendered licenses come from just six states - California, Arizona, Florida, Texas, Utah and Illinois.
In August, by the way, 7,615 people moved here. Jackman says so.