Even if you don't have $8 million, you can be strategic about the way you spend the money you do have that can make you happier.
For example, according to two of the researchers on the Harvard happiness study, Donnelly and Michael Norton, "giving to others leads to greater happiness than spending on oneself," they write in an article for The Wall Street Journal.
You can also use some of your cash to purchase your way out of an unpleasant task. That way, you spend more time doing things you enjoy, ultimately leading to happiness.
"Spending money on time saving purchases — like housecleaning, lawn-mowing and task outsourcing — promotes happiness by protecting people from the time-famine of modern life," Ashley Whillans, a professor at Harvard Business School and author of a study on money and happiness, tells CNBC Make It.
"Both the most and least wealthy individuals we studied derived benefits from spending money to buy time," meaning it has "broad benefits for well-being," she says.
After all, "What matters for your well-being is what you're doing with the minutes and days of your life," University of British Columbia psychology professor Elizabeth Dunn tells CNBC Make It. "If you have a lot of money and a lot of nice stuff, but you're spending your time doing things that you dislike, then your minute-to-minute happiness and overall happiness is likely to be pretty low."
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