Increases in safety and security of travel have had important effects on tourism demand over the centuries. As mentioned earlier, Cunard’s steamships were much safer than the wooden sailing vessels previously used in the transatlantic trade. Rail travel was much safer than travel by horse or horse-drawn carriage. Modern jet aircraft are also much safer that the propeller-driven aircraft they replaced. And this air travel safety record improved regularly over the years as airlines and aircraft manufacturers learned from the few accidents that did occur. In recent years, deaths associated with scheduled airline service have become quite rare. For the 10 years from 1997 to 2006, U.S. scheduled airlines averaged less than0.017 fatal accidents per 100,000 departures