Beware of the "funny math" that seems to come with PHEVs. I don't know how Audi calculates their "EV miles", but I know that Chevy and Ford calculate them very differently.
If you have a depleted battery, with the car operating in hybrid mode, the Volt will report zero EV miles. Ford will cheerfully tell you that every mile your hybrid drives without the engine running is an "EV mile". So in the first case, "EV miles" refer to miles driven from grid electricity - the way that I, and presumably most of us here, would think of it. In the second case, "EV miles" refer simply to miles driven without the gas engine running, even if the energy in those electrons originally came from burning gasoline (via the engine directly charging the battery, or indirectly via regen). I have taken trips in my CMax Energi with a depleted battery that Ford reports as high as 75% EV miles. I love the car, but this blatant green-washing drives me mad!
From the wording in the article, it sounds like Audi is actually being more honest here :shock: Or maybe it's a third-party data logger?