Year	Number
2000	15.79726
2001	16.48796
2003	16.41895
2008	14.46957
2009	13.8416
2010	13.59361
2011	13.56069
2012	13.15755
2013	12.91569
2014	12.3303
2015	11.9414
2016	10.82794
2017	10.1345
2018	9.87655