Arul, you should really set your own target as most companys outbound scripts will be different. The script should be timed, maybe with a few test calls. With this average you could divide this time (including your predicted idle time) by the staffed time (taking into account all shrinkages) per hour, to give you a target number of calls per hour, and depending on your tastes, a small amount of contingency should be built in.
hope this helps