Dear Mona,

What is the average age difference among couples? My partner and I are 28 years apart, so I’m sure we’re an outlier, but by how much? And is it different between heterosexual and homosexual couples (we fall into the latter)?

Thanks,

Seth, 32, Dallas

Dear Seth,

The average age difference (for a heterosexual couple) is 2.3 years, with the man older than the woman. In 64 percent of heterosexual couples, the man is older. In 23 percent, the woman is older, and in the remaining 13 percent, the partners are less than 12 months apart in age.

This data comes from the 2014 Current Population Survey (CPS) and is based on information provided by 31,075 male-female couples. Those surveyed couples are supposed to represent the estimated 70 million heterosexual couples who live together in the U.S. It doesn’t matter whether they’re married or unmarried, parents or childless — all couples are counted in the CPS, unless they’re gay.

So, I’m sorry, Seth, but these numbers just don’t properly represent you. I ran into a similar problem when I wrote about the average height difference in couples. So I have to switch to a different data set if I want to include gay couples in my analysis (and I do!).

In this case, Facebook has some answers that might be of interest to you. Using anonymized data from U.S. users who say they are in relationships, Facebook found that the average age difference in gay couples tends to get bigger the older people get. Those in their early 20s have an average age difference in their relationships of about two to three years, but once people get into their 40s, that average age gap increases to about seven years. The age difference increases for older male-female couples, too (shown in red below), though not by as much. (Remember, this is self-reported data from people who make their relationship status public on Facebook.)

Your relationship probably is an outlier, Seth. But using these averages, it’s hard to say how much of one. There could be lots of couples who, like you and your partner, are increasing the average age difference but are still in the minority.

It’s easier to spot heterosexual outliers because I have the original data provided by the CPS. Of all those couples surveyed, the biggest age difference was 58 years. I took a closer look at that particular case and found a 21-year-old man married to a 79-year-old woman. The age gap in your relationship might not look so big now, especially when you consider that 1 percent of heterosexual couples have an age difference of 28 years or more.

Hope the numbers help,

Mona

Andrew Flowers and Ben Casselman contributed analysis.

Have a question you would like answered here? Send it to @MonaChalabi or dearmona@fivethirtyeight.com.