Washington, D.C. ā€“ According to a recent research study of the relationship between travel and shopping, more than half (51 percent) of shopping travelers say that shopping was the primary or secondary purpose of one or more of their trips taken last year. The study, The Shopping Traveler, was based on a representative sample survey of 1,000 U.S. adults who took at least one trip in 2000. It was conducted by the locally based Travel Industry Association of America (TIA) and commissioned by Bloomfield Hills, Mich.-based Taubman Centers Inc. The study also revealed that travelers who shop spend a lot on their purchases ā€“ an average of $333 during their trips, with 22 percent spending more than $500.