Nice stats. There are 2 things I think worth mentioning and maybe would look nice to be correlated to some of the graphs.
One is the fact that more people are commenting than creating posts. I think is a sign of maturity. As steem grows, you can not be noticed when you write small, low quality posts. It's easier to contribute to a strong topic in somebody's else post.
Second, I think the activity is correlated with the steem price. The rewards for the posts are getting low so more people get discouraged as they see they earning are getting low, so they stop posting and being less active...
I'm new and changed my strategy last week. I was trying hard to post a lot. Now I try for 1 post a day but post many more comments than that.
I got the suggestion of 10-30 comments a day and than later saw a post suggesting 100 comments a day!!!! I'm not up to that, but I'm still going to focus in that direction. I earn more steem money (still not understanding it) and I learn more about this place by commenting than by posting.
With everything I do post - I focus on keywords for the search engines. Steemit is small with readers, but the alexa and moz ranking mean that people from the outside will see my work better than my own 6 year old sites.
I'm really encouraged to be here even though the learning curve is a sledgehammer to my brain. I'm really a weight loss and health author and blogger and know nothing of crypto etc. I guess I will soon learn this new skill :)
interesting observations - now that Steem (http://coinmarketcap.com/currencies/steem/) along with other cryptos have shot up, it'll be interesting to see if that positively impacts Steem's posts, active user total, etc. I'm guessing YES :)