Year	Number of
1990	14982.63
1991	15461.38
1992	15959.76
1993	16477.16
1994	17004.64
1995	17553.28
1996	17962.93
1997	18390.55
1998	18827.61
1999	19263.32
2000	19719.73
2001	20000.58
2002	20302.8
2003	20609.67
2004	20912.95
2005	21228.03
2006	21422.64
2007	21606.88
2008	21793.75
2009	21983.06
2010	22177.14
2011	22691.04
2012	23233.9
2013	23782.11
2014	24335.81
2015	24895.18
2016	25472.09