Year	Number
1996	4063.96
1997	4411.82
1998	4572.31
1999	4573.08
2000	5285.59
2001	5720.28
2002	6408.11
2003	6750.01
2004	7964.63
2005	9194.86
2006	10567.48
2007	11053.49
2008	11721.47
2009	11977.04
2010	11836.24
2011	11879.61
2012	11776.04
2013	11695.4
2014	11418.51
2015	11100.49
2016	11006.77
2017	10902.78
2018	10952.68
2019	11490.71
2020	12538.66