Year	Number of
1990	147.38
1991	151.5
1992	152.34
1993	159.39
1994	159.72
1995	162.97
1996	166.29
1997	164.09
1998	161.8
1999	165.31
2000	169.92
2001	175.17
2002	172.21
2003	175.18
2004	176.72
2005	176.69
2006	181.88
2007	186.62
2008	192.91
2009	197.16
2010	198.92
2011	204.92
2012	208.06
2013	208.27
2014	210.96
2015	211.14
2016	212.57