Year	Number of
1990	195.6
1991	206.15
1992	207.75
1993	211.54
1994	213.08
1995	219.57
1996	223.97
1997	232.34
1998	234.4
1999	237.83
2000	242.62
2001	249.8
2002	258.79
2003	269.08
2004	275.59
2005	281.38
2006	291.1
2007	305.6
2008	320.43
2009	329.19
2010	346.23
2011	354.49
2012	364.33
2013	375.97
2014	384.81
2015	387.45
2016	391.75