Officially it is $65 per kW per month (measured kW and not estimated).  With 9 S7s, 2 A721s, and 11 S9s it works out to $0.32/TH/day or $0.079/kWh.

Edit:  If I can get all of those S7s replaced with S9s or some of the newer A8s, my hash rate would go way up with little to no increase in hosting fees.  That's the goal but damn it's become nearly impossible to get new equipment from anywhere!

Edit2:  As you work your way through the numbers, all of my S9s range from 1290W-1520W and my S7s range from 1210W-1470W.  Both of my A7s are 1000W each.  There is a lot of range in the power usage of this equipment and there is no perfect answer but after 3 years of paying this host, I know how much it costs.