Since the attacks of September 11, 2001, tourist travel to the United States has been 20% lower than previously, and Americans‘ outbound tourist travel has been down about 14%, economist Alan King of the University of Otago in New Zealand reports on the basis of a study of travel payments and receipts.
Other studies that have shown just a transitory effect on tourism don’t take into account the dollar’s depreciation after the attacks, King says.
Source: HBR, The Daily Stat