An ancient Chinese proverb confirmed by a modern positive psychology. Learn more from the talk by Prof. Sonja Lyubomirsky.
If you want happiness…
for an hour – take a nap
for a day – go fishing
for a month – get married
for a year – inherit a fortune for a life time – help somebody else
A side note: you can be happy longer when you marry the right person and you are supportive for each other.