Butter bread, look at where the unexchanged STARTED the day for miner 2,5,6 that got the good payouts. For those 3 the unexchanged started and finished the same or lower than the day.
Now look at your miner, miner 0, you started with near 0 and ended up with near 0.3. So you need to add taht 0.3 to your 0.32 you got paid out (since it will get paid at a later date). That makes 0.62
0.62 is pretty similar to miners 2,5,6 you refer to.
Pretty much what chillin' said. You need to add up the immature, unexchanged, and balance at the beginning and end of each day, and compare.
Also, this analysis is fundamentally flawed because mining is time-dependent. Run the miners on 6 new addresses for several days (STARTING AT THE SAME TIME) and compare those graphs. That would tell you a lot more.