Yeah, they are powering down fair amounts but it is also that some like myself are powering up too. Plus, there are other factors like with every sign up through steemit they are getting a delegation which I think is also factored in. so 100,000 sign ups is 1.5 million in delegation. That must have an effect too right?
It is hard to say precisely though but, I don't mind the whales powering out if the smaller fisher are powering up. Low price means more opportunity for them to earn more steem and combined with high SBD, buy in is pretty good if using earning here. Unfortunately, the vast majority aren't it seems.
You might be right about the effect of new users. They seem to lower the power from whales. But aa many of them become inactive they probably don't.