Yet, you stated that the data were poorly sampled and focused on a particular subset. I'm wondering how you know that.
I looked at those dates, they cover 2 months period which is 1/6 of a year. Both, Nxt and Iota, are innovative projects, so it's not surprising that they attract people. Common sense says that finding 10 users that registered within 2 months and got attracted by Nxt and Iota is not so improbable as you want to say. Resume: look my posts above.