Year	Number
1970	9.39323
1971	8.66061
1972	9.0879
1973	10.2702
1974	10.20961
1991	13.84572
1993	10.30501
1998	17.45996
1999	11.01705
2000	11.88346
2001	12.8672
2002	11.86107
2003	11.83609
2004	11.83621
2012	18.4041