Year	Number
1996	20.58
1997	17.64
1998	22.14
1999	21.37
2000	26.82
2001	26.94
2002	27.45
2003	38.34
2004	35.14
2005	39.99
2006	53.23
2007	112.66
2008	95.32
2009	98.08
2010	89.87
2011	101.33
2012	127.24
2013	162.96
2014	115.13
2015	99.09
2016	115.86
2017	146.13
2018	146.69
2019	186.61
2020	209.71