I would be careful about any site that gives network hash rates on any of the POW/POS chains.

The calculations at best are a rough guesstimate as the difficulty difference between POS and POW blocks completely throws the difficulty part of the hash rate formula off. At best (Unless somebody has beat me to implementing a fix     ), one can try and grab an average of POW difficulty over the last 24 hours or more and use that as the difficulty in the hash rate formula.

I have one fix thought out already, but I would rather come up with a different one. However, this fix is pretty much on the top of my list now, so I guess I will implement it on CCE sometime this week.