Year	Number of
1990	148.25
1991	152.79
1992	158.74
1993	168.32
1994	176.76
1995	186.73
1996	200.31
1997	214.17
1998	225.96
1999	234.57
2000	244.59
2001	252.18
2002	256.79
2003	260.17
2004	263.67
2005	267.86
2006	272.71
2007	276.45
2008	278.96
2009	284.08
2010	288.59
2011	290.86
2012	298.93
2013	307.67
2014	319.21
2015	326.98
2016	336.4