Year	Number of
1990	211.42
1991	209.37
1992	201.55
1993	197.06
1994	193.33
1995	195.45
1996	198.64
1997	201.12
1998	217.38
1999	237.2
2000	256.95
2001	280.83
2002	309.22
2003	326.51
2004	352.86
2005	345.74
2006	342.96
2007	336.09
2008	338.01
2009	345.4
2010	341.22
2011	336.94
2012	336.68
2013	337.89
2014	355.8
2015	362.93
2016	373.05