Year	Number of
1990	295.18
1991	308.4
1992	322.07
1993	336.49
1994	351.58
1995	367.5
1996	366.05
1997	364.89
1998	364.16
1999	363.46
2000	362.78
2001	371.68
2002	381.01
2003	391.16
2004	402.04
2005	413.8
2006	429.25
2007	445.97
2008	464.47
2009	484.03
2010	504.75
2011	525.48
2012	547.7
2013	570.89
2014	596.14
2015	623.65
2016	653.03