I'd like to see whether there's a correlation here between gender imbalance in the particular subject and the marriage rate. I suspect theology is a heavily male-dominated subject, since a large number of the associated careers are either formally male-only or traditionally male-dominated.
I'm wondering if this might be a case where the men outnumber women so much that a high proportion of the women in the field can easily find suitable men to pair off with without going further than their college.
Checking whether other male-dominated subjects have similarly high intra-major marriage rates would test this(I don't know what they are, offhand, but I suspect a lot of STEM subjects might be there), and also doing the gender-reversed study (where it goes by the first marriage of the husband) might get similar results with more female-heavy subjects.
I don't know if it is male dominated, Missionary activity increasingly is dominated by single women, and while pastors and leadership are often male, the entire parachurch and support aspect is probably female dominated.
Religion in the west for the most part is intensely driven by the needs of women, and men for the most part take a figurehead role as leader, while being conspicuously absent from the rank and file. You can look at Christian culture overall to see this, everything from Christian bookstores to Christian movies is overwhelmingly targeted to women, who make up the majority of the market.
If anything my bet is the competition for men is fierce, and ministry tends to be something many women choose instead.
I can't seem to find any hard numbers at the moment, but I believe that the gender ratio for theology is fairly close to even (or, at least quite a bit closer than engineering or other male-dominated disciplines).
Keep in mind that, while there are variations among the individual majors, but in general women tend to be over-represented in the humanities. Also, relatively few humanities majors actually end up working in a discipline that requires their major.
Unless graduates suddenly have their genders reassigned to balance the ratio in their field, this is still relevant. It's not a coincidence that male-dominated fields draw workers from male-dominated majors.
It seems to fit my impression too. But it feels like for STEM this would apply to women.
Most of my girl colleagues from college are married to classmates or other engineers.
For men, they usually are married with women from other areas.
I'm wondering if this might be a case where the men outnumber women so much that a high proportion of the women in the field can easily find suitable men to pair off with without going further than their college.
Checking whether other male-dominated subjects have similarly high intra-major marriage rates would test this(I don't know what they are, offhand, but I suspect a lot of STEM subjects might be there), and also doing the gender-reversed study (where it goes by the first marriage of the husband) might get similar results with more female-heavy subjects.