Year	Number of
1990	152.76
1991	162.36
1992	173.93
1993	187.42
1994	201.91
1995	215.66
1996	225.27
1997	230.89
1998	236.28
1999	242.57
2000	247.34
2001	250.73
2002	255.55
2003	258.29
2004	262.3
2005	267.18
2006	274.45
2007	282
2008	291.32
2009	302.38
2010	313.96
2011	324.2
2012	334.62
2013	343.99
2014	354.78
2015	366.44
2016	381.78