A softening economy may be forcing retail sales to dip slightly. But some major shopping centers are bringing in the bucks by leveraging Americans' desires to consume as they hit the road for summer vacation.

Across the country, retail real estate vacancies are on a slow but steady rise in all categories except local shopping centers. This is putting downward pressure on rents, forcing profits to fall for even healthy retail real estate firms. In fact, in the first quarter, retail rents across the nation fell an average of 0.38 percent, according to CB Richard Ellis Services.

In April, national same-store sales for apparel stores rose only 2.9 percent, compared to a 6.6 percent gain during the same period last year, according to Instinet Research's Redbook report.

Scale-backs by some big-name retailers are signaling trouble in the industry. The typically hot Manhattan and San Francisco markets are seeing chic stores pull out in favor of lower-cost properties, reversing a decade-long trend of expansion.

But super-regional large-scale shopping malls stand to see a banner summer. Despite the overall softening in the market, Americans and foreign tourists still are going on vacation in record numbers. And a rather disturbing finding by the Travel Industry Association reveals that shopping is the most popular activity for both U.S. and international travelers.

The effect of tourism on super-regional malls can be seen in statistics from The Mills Corp. (NYSE: MLS), a self-managed real estate investment trust (REIT) that owns and manages 17 million square feet of retail space in 10 states. The Mills' shopping centers are located along major interstates in the South and East.

A testament to our country's focus on buying lots of stuff, more than 200 million customers visited the 12 Mills malls last year -- more than attended games in the National Football League, Major League Baseball and the National Basketball League combined.

The company's Concord Mills property is billed as the No. 2 attraction in the state, second only to the Blue Ridge Parkway, according the North Carolina Department of Commerce. And Sawgrass Mills in Florida ranks third in its state as a tourist attraction, just behind Disney World and Universal Studios.

Statistics like these are prompting shopping malls of all stripes to build out food courts, movie theaters and other attractions that encourage tourists and people with too much time on their hands to spend the day at the mall. The Mills Corp. calls it "shoppertainment."

"By design, tenant mix and sheer energy, our properties are unique - and a minor detour off major interstates," said Russell Lee, assistant vice president of tourism for The Mills Corp.

Nevertheless, retail property owners should continue to feel the pain that a downward turn in sales inevitably causes. Those who wish to sell off their shopping centers may have a hard time finding buyers. For instance, in Southern California, sales of shopping centers dropped by more than 38 percent last year -- the second year in a row that the number of sales declined.

The good news is that sale prices went up, indicating that owners won't sell unless offered a sweet deal. As long as owners are expecting a 9 percent to 10 percent return on their investment each year, things can't be too bad in retail.

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