Year	Number of
1990	2173.84
1991	2246.48
1992	2313.07
1993	2362.16
1994	2417.31
1995	2495.58
1996	2578.05
1997	2681.34
1998	2799.49
1999	2938.71
2000	3090.5
2001	3193.66
2002	3319.45
2003	3464
2004	3642.86
2005	3815.32
2006	3988.47
2007	4145
2008	4309.86
2009	4507.22
2010	4711.59
2011	4927.65
2012	5176.06
2013	5401.01
2014	5651.68
2015	5931.18
2016	6173.69