MINNEAPOLIS (WCCO) — Before every holiday we hear the same reports: a projection of how many Americans are going to get in their cars or hop on airplanes to travel.

The prediction comes from AAA, but how do they know how many people are going to travel?

“We did not make it up,” laughed Gail Weinholzer, public affairs director of AAA Minnesota and Iowa. “Nor did we stand on an overpass and count the cars going by. We’ve honed it down to a science.”

AAA has been doing projections for holidays for more than two decades.

“They began in 1989 to the best of my recollection, but the first one to become the subject of a national news conference was done jointly by AAA and the Travel Industry Association prior to Memorial Day of 1990,” said Sundstrom, now the Director of Public Relations for Delaware’s Department of Transportation. “It was a forecast for the number of travelers for that weekend as well as the entire summer travel season. A key component then, as now, was the outlook for fuel prices which was my responsibility at the time.”

In 1990, the first forecast didn’t make much of a blip. But by 1991, they were a national phenomenon.

“The forecasts were initially faxed and mailed to media as a news release, but quickly became so popular that we recognized the need to convene a news conference,” he said.

More than two decades later, the release still creates waves for every holiday: Memorial Day, Independence Day, Labor Day, Thanksgiving and Christmas.

“The public relations motivation was a desire to highlight AAA’s considerable expertise as a travel information provider not only for motorists, but for all travelers through the association’s travel agency network,” said Sundstrom.

Typically, holidays are very slow for the news media. AAA was seeking a higher national profile; it is the nation’s largest travel agency. The projection filled the news void.

I’m proud that our work has become almost as much of an American holiday tradition as fireworks, turkeys and Santa Claus, and possibly one of the greatest corporate PR activities of all time.

The original research looked at drivers only, going 100 miles or more. There were 19.5 million drivers in 1991. Today, the threshold is for a trip 50 miles away from home, and the number usually hovers around 40 million.

AAA hires an outside firm to run the analysis. IHS Global Insight does the work. According to the company, their forecast leans heavily on economic variables — things like employment, the stock market, and gas prices. That data is combined with historical travel information gleaned from a monthly telephone survey of 50,000 Americans.

But who’s checking the work?

“We do a post-survey as well with the next holiday,” Weinholzer said. “For Christmas, we’ll ask them: ‘Did they travel for Thanksgiving?’”

Jason DeRusha