If we could factor out all power ups and downs, would the data look different?
I'm interested in that, too, but so far I've no idea how to do that.
However we can estimate the effect of content and curation rewards on redistribution of power. At current mining rate of 800 STEEM/minute it's 800 * 60 * 24 * 7 = about 8 million STEEM per week. Of that amount, 7.75% (is this the actual number?) go into content/curation rewards - this is 625k STEEM. According to steemd.com, total_vesting_fund_steem is now 125 million STEEM, of which 625k is exactly 0.5%.
So even if all rewards went to a single group of steemians, e.g. to dolphins, that would increase their share by no more than 0.5%. Any increase beyond that point should be attributed to other factors, such as powering up/down or changes in activity.
My math might be off quite a bit, would be great if someone checks if it makes sense