BOSTON – A lackluster national economy and slowly rising gasoline prices are likely to keep many Americans at home over the Memorial Day weekend.The American Automobile Association (AAA) has projected that the number of Americans traveling on vacation during the weekend will increase by 1.5 percent from 2008, with 32.4 million travelers taking a trip of 50 or more miles away from home. Last year, 31.9 million Americans traveled during the same period, a dramatic decline from the 35.3 million who vacationed in 2007.”Last year, soaring gas prices and a deteriorating economy resulted in far fewer trips being taken than had been forecast,” said Robert L. Darbelnet, AAA president and chief executive officer. “The good news is sharply lower gasoline prices and plentiful travel bargains have Americans feeling better about taking a road trip this summer, which should help tourism-based economic activity throughout the nation.”According to Darbelnet, approximately one in seven Americans is employed directly or indirectly by the hospitality and travel industry. The AAA projections are based on research conducted by IHS Global Insight, a Boston-based research and consulting firm.Most of the holiday travel will be by automobile. Approximately 27 million Americans, representing 83 percent of all travelers, are planning a road trip. AAA does not expect gasoline prices to surpass an average $2.50 per gallon, with the current nationwide rate at $2.25 per gallon for self-serve regular.Travel by air is predicted to decline by one percent. Approximately 2.1 million Americans will travel by air over the holiday weekend, representing 7 percent of total travelers.The average distance traveled by Americans on the Memorial Day holiday weekend, May 22-25, is forecast at 620 miles, a slight decrease from 2008 when the average distance traveled was 640 miles.The AAA also noted that air fares, car rentals and hotel rates were expected to slightly decrease in price during the holiday weekend.