[ Note: I am Episcopalian, not Lutheran. If you're looking for a specifically Lutheran perspective, I'll step away from the discussion. ]
[ Second note: According to his obituary (
https://obits.al.com/us/obituaries/huntsville/name/jon-ahlquist-obituary?id=8016377), Ahlquist belonged to Calvary Bible Church, so he also was not Lutheran. ]
I could only find one article which gave actual numbers, in my quick search this morning for some data:
Faculty Faith . According to their survey, "more than half of the academics believe in God and less than a quarter are either atheist or agnostic", though they note that this is a higher percentage of atheists/agnostics than is found in the general population. A proper answer to the "why" of academics' beliefs would, as the article notes, "require a longitudinal study over decades". I'd be interested in reading the results of such a study.
As we collect numbers, it's important to remember that there are lots of categories of religious belief besides young earth creationism and atheism. Non-atheists include Catholic, Orthodox, and mainline Protestant Christians; Jews; Muslims; Hindus; Buddhists; and an assortment of smaller religions. All of these religious groups are represented among my faculty colleagues at the university where I teach.