Year	Number of
1990	222.32
1991	225.88
1992	204.67
1993	211.05
1994	218.59
1995	218.15
1996	205.84
1997	185.37
1998	170.78
1999	169.49
2000	166.78
2001	169.59
2002	169.43
2003	174.98
2004	172.89
2005	180.72
2006	185.46
2007	189.83
2008	191.16
2009	192.56
2010	200
2011	184.16
2012	187.93
2013	183.95
2014	190.85
2015	192
2016	189.91