retail leakage
n. The loss of local retail sales that occurs when people shop in an area other than the one in which they live.
Examples
2004
Results are trickling in from an extensive scientific study of the shopping habits of Helenans, a study local development experts hope will lead to strategies to keep more shoppers here — and draw more shoppers from other Montana cities.

"We had heard anecdotal stories about people leaving Helena to shop," said Sheldon Bartel, executive director of Gateway Economic Development Corp., one of four entities to fund the research. "The study was designed to test those anecdotes, and to find out if people shop do outside the community, why. We were looking to reduce that retail leakage with the hope that more money would stay in the county and more jobs would be created locally."
—John Harrington, “Helena, Mont., Shoppers Often Leave Area to Buy, Study Reports,” Independent Record (Helena, Montana), March 28, 2004
1999
DDA board chairman Bob Tointon said that whatever path the business community chooses, he hopes it will stem what he called the 'retail leakage' that has plagued downtown business owners. 'Our trouble is that all these new people who are coming to Greeley to live are going somewhere else to shop,' Tointon said.
—Tom Hacker, “Greeley ponders downtown facelift,” Northern Colorado Business Report, August 27, 1999
1984 (earliest)
While a $20,000 study revealed Chadron's business community is economically stable, consultants hired by the city discovered that the city was $22.5 million short of what it should expect in retail sales each year.

"There's that type of money that is going somewhere else,'' said Steve Erwin, chairman of the Chadron Business Improvement Committee.

City Manager Carl Dierks said two consulting firms, West Plan Partnership of Boulder, Colo., and Coley Forrest of Denver, Colo., proposed several ideas for Chadron to capture that retail "leakage.''
—“Chadron Studies Mall Proposal To Create Ag Shopping Center,” The Omaha World-Herald, February 06, 1984
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