Year	Number of
1990	123.39
1991	125.82
1992	128.23
1993	130.41
1994	132.62
1995	134.98
1996	142.98
1997	151.67
1998	160.98
1999	171.2
2000	182.59
2001	197.02
2002	212.8
2003	229.98
2004	248.74
2005	269.45
2006	284.77
2007	301.01
2008	318.28
2009	336.94
2010	357.47
2011	366.09
2012	375.45
2013	385.76
2014	396.75
2015	408.46
2016	420.1