I have traveled about the same amount and found that I was "randomly" selected more often than in the past. We were finally told at work that if we listed ourselves more than a couple of days in advance we would be less likely to get selected so I tried it on my last trip. It actually worked! I am usually that person who is chosen every single time but we went round trip without getting searched so I was a happy camper. Of course, if I had been chosen I would have had a problem since I was already running late and we got on during final boarding!