Ryanair has a strange obsession with comparing itself with British Airways.

The Irish low-cost carrier has happily adopted BA’s former slogan: “The world’s favourite airline”. On Monday it combined use of the slogan with the claim “Ryanair: now twice the size of British Airways”. By some measures, the latter is true, by others it very much is not. It could just as well have said “Ryanair: quarter the size of British Airways”.