It would be easy to reduce an area to one number out of a hundred. Here is what that number would quietly be deciding on your behalf.
Any single score has to answer a question nobody actually agreed on: how much does a flood zone matter next to an EPC band? Is a conservation area worth more or less than a deprivation decile? Pick weightings, and you have baked an opinion into something that will be read as a measurement.
The opinion then travels. A number out of a hundred gets quoted, compared, put in a spreadsheet column, and by the third hop nobody remembers it was a judgement call about weightings. It also ends up competing with the one figure in this whole picture that is actually certified and independently regulated, which is the property's own EPC band.
So the components stay separate, and the headline pairing on every area page is two real measurements rather than one invented one.
The first is what the certificates in an area currently score. The second is what the same certificates say those homes reach if the improvements already listed on them are carried out. Both come off the certificate as issued, the same document that sets the property's actual band. Neither is modelled here and neither is ours.
The distance between the two is what these pages call distance from standard. It is a measurement of how much documented improvement is sitting in an area's housing stock right now, and it is deliberately the only headline figure on the page, because it is the only one that does not require us to have an opinion.