Year	Number of
1990	45.78
1991	46.92
1992	48.31
1993	49.91
1994	52.33
1995	55.9
1996	59.87
1997	65.07
1998	71.96
1999	78.81
2000	86.34
2001	91.27
2002	95.43
2003	96.82
2004	95.55
2005	90.88
2006	88.51
2007	87.29
2008	87.52
2009	85.95
2010	86.45
2011	88.18
2012	93.96
2013	96.77
2014	101.83
2015	107.44
2016	113.32