Year	Number of
1990	22941.51
1991	23908.6
1992	24878.73
1993	25829.6
1994	26862.19
1995	28034.67
1996	28953.62
1997	29920.29
1998	30912.36
1999	31891.42
2000	32986.89
2001	33703.41
2002	34408.16
2003	35116.9
2004	35911.56
2005	36859.87
2006	37474.1
2007	38143.09
2008	38859.97
2009	39617.03
2010	40453.05
2011	41841.6
2012	43323.9
2013	44855.29
2014	46318.2
2015	47843.04
2016	49431.94