Year	Number of
1990	147.1
1991	166.07
1992	187.31
1993	212.29
1994	238.43
1995	265.65
1996	273.2
1997	281.07
1998	284.66
1999	288.57
2000	293.41
2001	297.62
2002	302.26
2003	307.85
2004	314.28
2005	321.99
2006	328.14
2007	334.88
2008	343.14
2009	352.29
2010	362.71
2011	372.33
2012	383
2013	393.82
2014	405.55
2015	418.24
2016	432.75