Year	Number
2000	13.30478
2001	13.30455
2002	13.30464
2003	12.98662
2004	13.07547
2005	13.91947
2006	14.38286
2007	14.68447
2009	23.59557
2010	22.24456
2011	22.39024
2012	23.17744
2013	24.40797
2014	24.46931
2015	23.7782
2016	23.68901
2017	22.80461
2018	22.78288