What economics has to say about same-sex marriage.

Love and companionship make most people happy and generally represent two of the key reasons why couples marry. In the economists’ view, love and companionship are a particular type of commodity: they cannot be purchased or traded on a market, but they can be produced by a household to generate happiness for its members.

According to new data from the U.S. Department of the Treasury, married gay men earn nearly 56 percent more money than married straight couples and 42 percent more than lesbian married couples.