Denver becoming United Airlines 'highest-margin hub'

United Airlines president Scott Kirby said Denver is turning out to be the carrier's "highest-margin hub" (Skift, 12-Sep-2019). During summer 2019, the carrier marked certain days with more than 500 flights, with its Denver-Frankfurt service launched in May-2019 also becoming "one of the five most profitable international routes" during this period. Mr Kirby noted that "this is what happens with a hub", saying: "You add flying to a hub and it makes everything else stronger".