Year	Number
2001	27.33886
2002	24.28769
2003	29.00539
2004	30.54693
2005	28.04705
2006	27.68118
2007	16.70846
2008	24.56404
2009	31.56211
2010	22.50121
2011	23.27832
2012	30.77434
2013	32.39752
2014	26.29595
2016	25.35538
2017	25.83913