These days, most of my posts get between 55 and 80 upvotes.
I know most of the powerful upvoters, because in a way or another I had friendly conversations with them.
I have even been visiting some of them such as 
However, there are four Steemians that from time to time upvote some of my posts and I have no idea who they are. These four guys have joined Steemit between September 2016 and March 2017 and they have between 90,000 and 185,000 STEEM Powers. But they have never posted and are not following anybody.
They are, in alphabetical order:
[By the way, I wonder what the hundreds of Steemians that follow those that never post or never comment expect]
As I said, I don't know who they are, but I am grateful for all the upvotes they make, to me or to other Steemians.
So, THANK YOU to 
, 
, 
and 
-- Vincent Celier