At least weekly usually multiple times a week. Sometimes daily or more often.

I keep a 2×aaa in my pocket organizer, and a small 1×aaa on a chain around my neck, plus a slightly bigger one in my go bag. I use them all frequently, but it's the neck light that gets the most use. 9/10 times, having it right there, shining down on what I'm trying to do is so convenient I can't believe more people aren't doing it.