round-trip bus fare: £4.70/day
number of days required to break even: £544 / £4.70 = 115.7
current number of round-trip commutes completed: 1365mi/11.8mi/commute = 115.6

NEXT COMMUTE WILL BE THE BREAK-EVEN COMMUTE!

wish be luck ... at that point, I will add a money saved statistic