How important is a college degree for an established admin?

Question: “I’ve been an admin for about a year, and am thinking about finishing my college degree studies at night. Since I really enjoy this field, I’m wondering if I’m better off just working hard and getting better at it rather than spending my nights for two years getting a degree mostly for the sake of having one. How much job experience do you think it will take to look as good on a résumé as a diploma would?” – Jane, Support Team Leader