An index is a measure of how a stock market is performing. Even the monsters know how to build up their portfolio.
When a kill is secured -- say a human being -- or a carcass is recovered, they are cut up into many pieces and have their blood completely drained, then these parts will be distributed among the shareholders...so far still with me?
So basically, they will trade these mutilated pieces among themselves, and occasionally, they will also offer performance shares, meaning free of charge, no obligation like a boss!
They would even accept bones in exchange for meats etc., so that the weaker ones will have to dig the grave if need be.
Now that humans clearly have the upper hand, using their cunning tactics and innovation to design better weaponry and traps to protect themselves against the monsters -- how can the monster index still growing strong?