I think your pool speed is off/wrong/lying.

User Id   Hashrate
19           79793

Your saying that you have 1 user is running 79GH/s.  Then it also says that miner has -2 shares:

User Id   Shares
19            -2

Wow, negative shares! That's new.

So when your pool runs @ "83.2 GH/s", the biggest user in the pool is 79GH/s with -2 shares...I don't believe for 1 second that you're really running a 83.2 GH/s.

Nice try though.  Please fix your pool speed indicator. People don't like it when you get this type of thing wrong.