CO2 emissions: g/km or oz/mile?

In case you struggle to understand HM Revenue & Customs table showing what percentage of your company car's list price counts as a benefit-in-kind for P11D purposes, because this entails first looking up your car at the SMMT website and they both use these new fangled 'grams' ('grammes'?) and 'kilometres', I have prepared a ready reckoner showing what this actually means in 'ounces per mile':I hope this helps!