Year	Number of
1990	217.63
1991	214.82
1992	200.47
1993	189.13
1994	179.35
1995	171.23
1996	172.61
1997	172.03
1998	170.47
1999	169.89
2000	168.99
2001	177.09
2002	184.02
2003	189.72
2004	195.61
2005	197.72
2006	192.57
2007	187.71
2008	183.73
2009	181.04
2010	178.75
2011	173.24
2012	169.53
2013	166.75
2014	165.14
2015	163.85
2016	162.92