Year	million passenger-km
1995	3321
1996	3103
1997	3147
1998	3241
1999	3104
2000	3208
2001	3979
2002	4079
2003	4258
2004	4682
2005	4357.6
2007	4767
2011	4574.19
2012	5039.45
2013	6257.38
2015	7407.39