... by the need to project estimates into the future to meet the reporting requirements. In Table 1.1 we break down the process of estimating the savings into a series of steps. The first step is to ... fundamental part of constructing the current-yearexpenditures is to control for any changes in the nature of servicespurchased over time, including changes in the scope of services, and, to the extent ... (Mooreet al., 2002) . While we (and others) have some concerns about the accuracy of the data, including the classification of expenditures as10 Measuring Changes in Service Costs either services...