Year	Number
1977	10
1978	5.25
1979	4.33333
1980	3
1981	2.25
1982	2
1983	4.14286
1984	8.27273
1985	14.15385
1986	6.42857
1987	6.77603
1988	8.75989
1989	7.54124
1990	8.30103
1991	6.82198
1992	8.16778
1993	8.00628
1994	7.84135
1995	8.9223
1996	9.08271
1997	10.54303
1998	12.26626
2004	16.20975
2005	16.20963
2006	20.04155
2007	15.68502
2009	16.50643
2010	16.8203
2011	18.45883
2013	15.85652
2014	16.18539
2015	16.15718
2016	16.2165