3.3 A key factor in benchmarking is agreeing the right comparators. Contracts may include details of what comparators should be used. If they do not, parties will need to find appropriate comparators. This should include both PFI and non-PFI contracts, adjusted where necessary to take into account different risk profiles. Comparators, where possible, should provide clear incontrovertible costs, so that valid conclusions can be made. It is not appropriate for comparators to only include the existing providers benchmarking data.