port. The PBX must not only have the capability to provide this output (most do), but it must be programmed to do SO. The Call Accounting software includes rate tables (details of the cost of telephone calls) which are applied to each call de- pending upon the duration, destination and time of day. Again, the Call Accounting pricing does not exactly match the cost of the call as it is billed by the long distance carrier or local tele- phone company. It usually comes within five to ten percent if the rates have been kept up to date and match the actual billing rates. 118 % The Telecom Handbook CHAPTER 6 Rates are computed through the use of V&H (vertical and horizontal) coordinates incorporated into the software. These pinpoint the geographic location of the destination for the pur- pose of assigning a cost to each call. If your company subscribes to one of the long distance carrier's many special pricing plans and you want your Call Accounting report pricing to approxi- mate your actual costs, you enter your own set of rates into the software (or arrange to have it done for you by the Call Account- ing system provider). Call Accounting software is hierarchical and can provide in- formation on many different levels. Not all systems provide the same number of levels or the flexibility in setting up report pa- rameters, SO it is important to determine what information you require before selecting a system. Most systems have four levels providing the following reports: Extension: A list of all telephone calls made by a particu- lar extension. Department: A list of the calls or summary of costs for each extension within a department. Division: A summary of the costs for each department in the division. Company: A summary of the costs for each division within the company. The dates for the report can be specified. The system will also have the capability for storing historical data and being able to provide year-to-date information for each category. Again, it is best if the desktop PC designated for the Call Accountin