Year	Number of
1990	28117.25
1991	27939.05
1992	27727.93
1993	27560.15
1994	27081.98
1995	26603.62
1996	26036.09
1997	25526.43
1998	25282.8
1999	25106.97
2000	24999.56
2001	24837.85
2002	24684.29
2003	24455.07
2004	24311.28
2005	24236.26
2006	23856.63
2007	23653.96
2008	23590.85
2009	23502.13
2010	23613.37
2011	23961.79
2012	24514.13
2013	25195.99
2014	25844.42
2015	26330.57
2016	26997.96