Year	Number of
1990	133.67
1991	142.6
1992	153.37
1993	166.17
1994	179.27
1995	191.23
1996	199.26
1997	207.97
1998	225.98
1999	239.63
2000	247.47
2001	250.9
2002	256.8
2003	267.9
2004	272.47
2005	281.45
2006	290.81
2007	300.55
2008	309.1
2009	315.44
2010	326.32
2011	336
2012	352.88
2013	359.88
2014	368.37
2015	386.24
2016	403.23