Year	Number
2003	45.50168
2004	46.16032
2005	43.23934
2006	40.09995
2007	39.67234
2008	32.61124
2009	31.00441
2011	29.28568
2015	29.69441
2016	28.26087
2017	28.27102
2018	26.89473