It's actually very common to be in a career not related to your college degree. There is individual level data in the Census Bureau's ACS PUMS data set for those interested in this kind of thing.

Self-promotion alert: I worked on a website that has some statistics about this. I found out that only 8% of chemical engineering grads (my undergrad degree) actually work in the field. (https://careertrend.com/major-chemical-engineering.html)