Year	Number of
1990	188.79
1991	194.05
1992	197.94
1993	200.82
1994	204.03
1995	208.31
1996	207.07
1997	206.82
1998	207.55
1999	208.72
2000	210.01
2001	218.46
2002	227.46
2003	238.09
2004	248.74
2005	259.45
2006	268.86
2007	278.81
2008	289.08
2009	299.45
2010	309.59
2011	313.41
2012	316.11
2013	317.98
2014	320.59
2015	325.13
2016	326.76