Year	Number of
1990	200.37
1991	207.05
1992	214.75
1993	224.02
1994	233.56
1995	243.51
1996	246.86
1997	240.75
1998	239.46
1999	240.5
2000	243.76
2001	249.61
2002	256.17
2003	266.38
2004	278.03
2005	289.76
2006	301.32
2007	313.11
2008	324.24
2009	336.16
2010	344.86
2011	356.03
2012	367.78
2013	380.29
2014	393.08
2015	406.63
2016	419.69