Want Marital Bliss? Pool Your Money

Last week, I went to Harvard Business School to talk to a number of academics, among them Michael Norton, the co-author of "Happy Money," a book about which I will probably be talking more in the coming weeks. We were discussing gifting, and one thing led to another, and I mentioned that my husband and I pool all our money. I was about to ask a question -- about why we enjoy giving each other gifts, when the money all comes out of the same pot -- but Norton interrupted with a delighted smile.

"That's good!" he told me. Apparently, there is research showing that the more you pool your money, the happier you are with your marriage. These effects seem to peter out at some very high level -- if you keep 5 percent of your income to yourself in order to have a little bit of discretionary spending, it won't make you any less happy than you'd be if you pool 100 percent. But people who pool 80 percent are happier than those who pool 70 percent, and so on. People who keep it all to themselves are the least happy.