Year	Number
1994	13.78784
1995	13.73505
1996	13.95326
1997	14.81622
1998	16.00586
1999	14.6349
2000	15.2859
2001	16.99821
2002	17.30822
2003	16.04386
2004	16.37781
2005	16.53773
2006	16.64297
2007	15.75433
2008	15.49275
2009	15.45938
2010	15.62688
2011	15.39785
2012	15.08
2013	16.29263
2014	15.67427
2015	15.15333
2016	14.83974
2017	14.60569
2018	14.49734