In the last forty years, the volume of travel has increased tremendously. Partly the result of improvements in transportation, this increase is also attributable to economic prosperity and social changes. Whereas only wealthy people journeyed for pleasure in the past, today people from most economic classes are able to travel. People are better education today. In general, the more education people receive, the more likely they are to travel. Paid annual vacations and public holidays give people more leisure time to devote to travel.