Predicting Book Fund Expenditues: A Statistical Model

ONE OF THE UNRESOLVED annual problems facing many library acquisition departments is how to insure that each acquisition fund is fully spent at the end of each fiscal year. 1 The significance of this problem increases as the buying power of acquisitions budgets continues to shrink. Of the methods used to spend budgets e:l;{actly, neither underspend nor overspend by more than a few percentage points, some border on the unethical, while others require vast expenditures of staff time. In some of the more fortunate academic libraries, the problem only exists for the total acquisitions budget, since the accounting for the individual fund allocatioms is at the discretion of the library. Nonetheless, i( the various book funds were allocated on some rational basis, each fund should be totally spent at the end of the fiscal year. What is needed is a simple method of providing the capability to predict at any time in the course of the fiscal year what the spent figure for each fund number will be at the end ofY that fiscal year, based on the spent figure to date and the orders that have been placed but not yet received. That is, for each item on order for each fund number it should be possible to predict how