You hear people say a lot that you should invest in experiences and not things, that they bring you greater happiness. I love that someone out there has studied how it affects your happiness and what about it makes you happy.
Apparently the greatest boost of your happiness is not the actual trip, not how you feel after the trip, but rather the anticipation of your trip. It boosts your happiness for eight weeks.
Source: How Vacations Affect Your Happiness
It seems like the best way to apply this information is to plan a trip every eight weeks.