Year	Number
2001	4.1931207791
2002	4.5029160395
2003	4.8127112998
2004	5.1225065601
2005	5.4323018204
2006	5.7420970807
2007	5.7420970807
2008	5.7420970807
2009	5.7420970807
2010	5.7420970807
2011	5.7420970807
2012	5.7420970807
2013	5.7420970807
2014	5.7420970807
2015	5.7420970807
2016	5.7420970807
2017	5.7420970807
2018	5.7420970807
2019	5.7420970807
2020	5.7420970807