There is no framework for sustaining joy, but Arthur Brooks, a Harvard instructor who teaches a class all about building a happier life, believes that any such plan should start with treating your happiness like a well-balanced investment portfolio.

Put simply, people should aim to invest in four areas that are equally important in order to feel more fulfilled in life, Brooks says in one of the happiness course’s videos.

“We need all of them, so our happiness can grow in a balanced way,” he says. “Each aspect of the portfolio is critically important to experiencing happiness. Just like any portfolio, it needs to be balanced.”

Invest in these 4 areas for happiness

1. Faith and life philosophy: Find what helps you make sense of the world, Brooks suggests. This can be a religion, spiritual practice or anything else that helps you find meaning in life.
2. Family: Strengthen your connections with your family. These are the “relationships that you don’t generally choose, but which you can count on,” Brooks says.
3. Community and friends: Develop strong friendships because they are typically your most intimate relationships. Friendships are relationships that you choose, and they can impact your happiness.
4. Meaningful work: Prioritize work that makes you feel fulfilled. This doesn’t necessarily mean a high-paying job because you don’t have to make much money in order to be successful and serve others, says Brooks.

Beyond the portfolio, there are other things that have a greater effect on your happiness, Brooks adds.

“A lot of your happiness isn’t under your direct control,” he says. “Approximately 50% of your happiness is inherited, and another big chunk is determined by your circumstances at any given moment.”

Though the happiness investment portfolio contributes to about only 25% of your happiness, it’s still worth prioritizing, Brooks notes. Pouring into each aspect of the portfolio with equal effort can improve how you feel, he says.

“None of these things can make up happiness all on their own,” Brooks says during the course. “They complement each other and exist in harmony.”

CNBC