Year	Number of
1990	226.48
1991	233.74
1992	242.6
1993	248.29
1994	257.33
1995	263.86
1996	268.19
1997	269.08
1998	274.05
1999	283.48
2000	289.79
2001	287.35
2002	295.62
2003	298.24
2004	296.71
2005	301.29
2006	299.48
2007	294.15
2008	299.81
2009	318.84
2010	334.49
2011	349.47
2012	357.28
2013	365.49
2014	377.5
2015	386.02
2016	401.35