The NYT compares the cost of being an unmarried homosexual couple to a married heterosexual couple.

Obviously, it's immensely important in the debate about same-sex marriage to make the comparison between the costs to a couple of living single and living married.

[W]e set out to determine what they were and to come up with a round number — a couple’s lifetime cost of being gay.

But, also obviously, the economic difference is between married and unmarried, not gay and straight, since a straight couple can choose to remain single. It's interesting to all couples to know the financial effect of marrying. I got married recently — to a person of the opposite sex — and it mattered to us. Now, also obviously, when a same-sex couple is denied the right to marry, they don't get to use the economic analysis in a choice of how they want to structure their lives. But it should be clear that the economic difference is useful to both heterosexual and homosexual couples. And, again, the comparison plays an important role in thinking about legalizing gay marriage.

I've always supported gay marriage myself, and I would even if the economic difference was minimal or great or infinitely complicated. But I can suspect that the NYT's exercise is aimed at convincing people that denying the right to marry is a great injustice, so I'm looking at this economic analysis with some skepticism.

There is an unintended effect to portraying marriage as such a great financial benefit: People who already have the right to marry may decide they ought to marry to rake in all those great benefits.

One thing is that the model they used had a couple with an income of "$140,000, which is about the average income in [New York, California, and Florida] for unmarried same-sex partners who are college-educated, 30 to 40 years old and raising children under the age of 18." $140,000? That's awfully high! There's an old stereotype about gay couples being wealthier than heterosexuals, and I'm surprised to see the NYT stoking it. But I suspect they tried various incomes and hit upon this number because it produced impressive results. Given that the median household income in the U.S. is about $50,000, I don't think you're going to persuade too many same-sex marriage opponents to cry over families that make $140,000.

Here is what we came up with. In our worst case, the couple’s lifetime cost of being gay was $467,562. But the number fell to $41,196 in the best case for a couple with significantly better health insurance, plus lower taxes and other costs.

Most of the analysis involves taxes and pensions and the like — things that vary according to whether the couple is married, but the article also includes the costs of acquiring children: artificial insemination and adoption. These costs are simply the costs of infertility — which can afflict heterosexuals too —and nothing that can be cured by legalizing gay marriage. But there are also costs to marriage that are not included, and that ought to caution people against assuming there are great financial benefits to marrying. First, and the article notes this, your taxes can increase — there's the marriage penalty. Second, there's the risk of needing a divorce, and that can be tremendously expensive, especially if children are involved. There is nothing in the article about divorce.

So, try to make the best decision you can about whether to marry, if you have the right to marry. Money isn't the only thing, but it's worth taking into account. I think there is a dollar amount for each of us which, if we had to sacrifice it in order to marry, we'd choose to live together as an unmarried couple. And maybe there is also a dollar amount for every couple that if they could save it by marrying, they'd go ahead and marry. When I was unmarried, I used to think that I would marry a male friend in a certain scenario: He needed expensive medical treatment, and I had the health insurance coverage to share.

And, again, as for gay people, I think they should be able to look at the same factors that heterosexual couples look at.