2.85% theoretical

Listed casino often quote this 2.85% win rate for VIP baccarat rolling. If the casino profit is down, one important factor is their actual win rate is less than the average 2.85%. My question is where they get this 2.85%?
It seems to me 70% of the time a casino will under achieve. I would expect a more 50/50 split between unders and overs. The figure 2.85% is not very reliable.

Go here and search for "Macau" (or go down near the bottom of the page). This appears to answer the question.