4.6 A key factor in benchmarking is agreeing the right comparators. Contracts may include details of what comparators should be used. If they do not, there are two approaches; the parties should look either:
a. to use as wide a range of comparative information as possible. This should include both PPP and non-PPP contracts, adjusted where necessary to take into account different service standards, rectification periods or risk profiles; or
b. to restrict the comparators to those few which provide clear evidence of competitiveness, in order to drive a result.
4.7 Although too often benchmarking is a huge and costly data-gathering exercise where much of the data remains unused because it is difficult to compare like with like, nevertheless approach 'a' is the preferred option as it gives a more complete spread of costs with less likelihood of distortion. In any approach comparators, where possible, should be clear incontrovertible costs so that valid conclusions can be made.