There may be a slight discrepancy. The article states that:
Recent statistics published by the U.S. Travel Association state that the travel industry is a $770,000,000,000 or 770 billion dollar industry. This number may decrease slightly in this time of economic recovery, but the number is certain to stay high.
Mr. Henderson has stated the industry is a 7 Trillion dollar industry. I wonder where the discrepancy lies? Nonetheless, regardless who is right or wrong... the market is huge.