Year	Number of
1990	14765.91
1991	15105.62
1992	15467.3
1993	15859.45
1994	16275.85
1995	16723.99
1996	17138.71
1997	17578.34
1998	18054.8
1999	18558.86
2000	19097.24
2001	19525.82
2002	19982.69
2003	20476.39
2004	20994.61
2005	21543.53
2006	22161.31
2007	22811.47
2008	23527.45
2009	24284.08
2010	25089.37
2011	26009.4
2012	26979.49
2013	28005.23
2014	29087.47
2015	30218.96
2016	31419.76