I would go on a limb to say its pretty obvious why there is a decline in the unique visitors...

The massive decline in value of STEEM and SBD and all these issues we keep reading about as Minnows here on the site, yea I bet people are getting bored and moving on.

Vote bots, spammers, whales who self vote only, the whale war.. whatever else issue there is.

But hey, those of us determined to make it one way or the other realize this is an opportunity to grow big.