Year	Number of
1990	91.19
1991	94.86
1992	99
1993	103.65
1994	108.82
1995	114.58
1996	122.22
1997	130.88
1998	140.33
1999	150.05
2000	159.91
2001	168.52
2002	176.86
2003	185.32
2004	194.53
2005	204.91
2006	207.45
2007	210.65
2008	214.55
2009	218.92
2010	223.7
2011	240.62
2012	259.39
2013	280.15
2014	302.92
2015	327.81
2016	354.88