Year	Number
1992	11.90193
1993	11.92051
1994	11.98013
1995	12.25695
1996	12.20721
1997	12.24817
1998	11.91323
1999	11.7153
2000	11.32153
2001	11.23336
2002	11.14215
2003	11.20606
2004	11.11823
2005	11.16327
2006	11.44453
2007	11.34596
2008	11.57367
2009	11.51261
2010	11.531
2011	11.54125
2012	11.5335
2013	11.72853
2014	11.90106
2015	11.97003
2016	11.62437
2017	11.55851
2018	11.55416