Miles Per Dave Gorman.
The distance travelled by British comedian Dave Gorman on his quest to meet other people with the same name, divided by the number of Dave Gormans he met on the way. The importance of the figure was reflected in The Graph, where Dave's obsession was focused upon keeping his mpdg within The Zone. The Zone was between 300 and 500 mpdg, and though he occasionally strayed out of it, I believe Dave met his target in the end.