Year	Number of
1990	15235.43
1991	15698.57
1992	16272.33
1993	16918.92
1994	17568.85
1995	18034.58
1996	18517.46
1997	19010.79
1998	19517.23
1999	20140.57
2000	20862.87
2001	21701.93
2002	22617.59
2003	23103.33
2004	23685.88
2005	24338.14
2006	24812.22
2007	25400.85
2008	26219.84
2009	27148.49
2010	28070.34
2011	28866.93
2012	29700.28
2013	30633.63
2014	31745.27
2015	32750.92
2016	34077.93