Year	Number of
1990	147.58
1991	153.95
1992	159.48
1993	168.37
1994	173.47
1995	179.64
1996	188.93
1997	196.46
1998	202.01
1999	210.99
2000	221.07
2001	234.24
2002	246.86
2003	264.76
2004	277.47
2005	281.57
2006	299.8
2007	314.78
2008	331.96
2009	347.44
2010	363.1
2011	379.1
2012	391.94
2013	391.43
2014	398.77
2015	402.96
2016	400.49