4TH/s for a week should, theoretically, generate 160-ish BTC.

The contract says they will hold back 20-30% for reinvestment.  That leaves 112 BTC for distribution.

112 BTC/10,000,000 shares = 0.0000112 BTC/share

That number won't be accurate since they are solo mining.  That means their income will have around a 25 BTC granularity.  160 BTC/week also assumes absolutely average luck.

Jere