Year	Number of
1990	98.82
1991	97.94
1992	92.34
1993	87.08
1994	84.15
1995	83.02
1996	88.02
1997	94.41
1998	104.07
1999	112.7
2000	118.43
2001	120.81
2002	122.61
2003	123.73
2004	125.56
2005	127.94
2006	133.65
2007	138.67
2008	144.92
2009	152.25
2010	160.07
2011	166.74
2012	173.15
2013	182.23
2014	191.49
2015	201.1
2016	210.29