2.19 The public sector comparator had a cost, in net present value terms, of £40.732 million while the successful PFI bid was £40.566 million; a difference of some £165,000 (or 0.4 percent) over the 25 year contract period. The Service provided us with a summary of the key comparator costs. The Public Sector Comparator used data on cost overruns in other court facilities in order to estimate the likely risks. It also identified a major additional sum to account for the security risk associated with the particular location. In total, the public sector comparator included quantified risks of £4.2 million. However, the Service was unable to provide a breakdown of the values of risks transferred, shared or retained. Although it is not possible to determine whether the methodology was correctly applied there is no reason to doubt that the basis of the figures was reasonable.