Year	Number of
1990	483.28
1991	489.88
1992	496.2
1993	498.57
1994	505.76
1995	509.16
1996	509.03
1997	503.5
1998	493.85
1999	473.6
2000	465.02
2001	463.15
2002	455.36
2003	452.05
2004	460.12
2005	464.67
2006	459.58
2007	447.54
2008	431.28
2009	413.33
2010	408.86
2011	399.58
2012	393.98
2013	377.72
2014	362.37
2015	364.87
2016	386.99