Year	Number of
1990	273.59
1991	281.12
1992	289.26
1993	298.28
1994	307.87
1995	318.26
1996	326.71
1997	335.87
1998	346.32
1999	357.26
2000	368.93
2001	386.65
2002	405.69
2003	427.49
2004	450.31
2005	474.41
2006	498.72
2007	524.14
2008	552.7
2009	583.06
2010	615.65
2011	644.66
2012	675.59
2013	708.57
2014	743.5
2015	780.51
2016	816.6