1. A method for predicting call volume, comprising: generating a staffing impact chart that indicates, in a visually indicated display, an expected difference between call volume and available agents for a plurality of time intervals in a future period of time based on a plurality of inputs, the plurality of inputs including: historical call volume data to a call center, a prospective schedule of agents servicing the call center, and an average handing time of calls to the call center by the agents, wherein historical call volume data which is skewed data is ignored and predetermined representative data is substituted for the skewed data; providing a variable table having a plurality of variables, each variable including a scaling value that modifies at least one of the plurality of inputs used in generating the staffing impact chart; selectively changing, by a user, at least one of the variables in the variable table; and immediately updating the staffing impact chart to reflect modified expected differences for each of the plurality of time intervals based on application of the change to the plurality of inputs.