Research shows that in the U.S., money correlates with happiness until you get to an income of about $75,000. After that, happiness returns diminish rapidly. The key is what you do after you hit $75,000:
Interestingly, and usefully, it turns out that what we do with our money plays a far more important role than how much money we make. Imagine three people each win $1 million in the lottery. Suppose one person attempts to buy every single thing he has ever wanted; one puts it all in the bank and uses the money only sparingly, for special occasions; and one gives it all to charity. At the end of the year, they all would report an additional $1 million of income. Many of us would follow the first person’s strategy, but the latter two winners are likely to get the bigger happiness bang for their buck.