With the "you have to hold 90% rule" i can´t imagine the volume is from people trading their 10%.
If I had to guess, I would say the dev is a millionaire by now.
We´ve seen 2.5 million in transactions.
So all the little sheeps made a scammer rich and think they are so smart.
It´s sad how easy you can use people to your advantage.
You can clearly see the drop is coming from people infringing the 90% rule. Check http://deeponion.info/.
1/3 of the airdrop participants moved more than 10%. That is a lot of people, than won't receive any airdrops in the future. A drop of 33% is not much in comparison to that. Specially in comparison to the run in the last month. And the drop is also not spectacular in comparison to the current volume. Since there were only 6 airdrops, they aren't many coins in circulation.