Sub 10K miles in a year, once a year oil change, else if the rate of driving is exceeding 10K per year, I change it every 5K. I would stick to one of those methods to keep your head easy. My car, I do it every 5K as it's a daily driver. The significant other's car, I do it once a year as it's a short trip vehicle. Easy numbers, either every 5K or every year. It helps with the other maintenance items as well due to easy scheduling, such as air filter change, tire rotation, cabin air filter, etc.