Hi, your score history doesn't seem to go back far enough but I'm guessing that you reached 50 ranked rounds as a tour master yesterday or day before. What this means is that from that point on, your average is calculated from your best 50 rounds only.
So, even if you score higher than your average (e.g. 35, 36, 37 x2) your average can go down because the 35,36,37 will push out worse rounds (e.g. avgs in 80's) from your top 50. Now, after 50 rounds as a tour master, your average can no longer go up, and is referred to as "saturation" among players.
When your avg. gets below 61 you should advance to legend and it will reset. Your first round as legend will be your new average. As legend you have to play 500 ranked rounds to reach saturation.
-Keith