Bing Travel has a Buy suggestion on these flights, with an 85% confidence they will stay the same or rise in the next 7 days (definitely not a fully reliable source, but I've had good luck with it). Controlling fare buckets is a way airlines can maximise revenue on money-making flights (Vail in winter seems like the best time for them to make money on that route--especially since AA is the only carrier that operates non-stop LAX-EGE). If your dates are fixed, now may be the time to pull the trigger, irrespective of fare bucket.