Year	Number
1961	118.30357142857142
1962	130.51643192488262
1963	140.56603773584905
1964	168.84816753926702
1965	159.53488372093022
1966	201.60427807486633
1967	232.3529411764706
1968	233.84146341463415
1969	240.96385542168676
1970	270.85526315789474
1971	329.7692307692308
1972	378.2608695652174
1973	452.6315789473684
1974	447.3684210526316
1975	446.80851063829783
1976	441.48936170212767
1977	427.0833333333333
1978	406.12244897959187
1979	395.7731958762887
1980	495.40540540540536
1981	522.9411764705883
1982	511.4925373134328
1983	486.25
1984	469.69696969696975
1985	488.8888888888889
1986	476.5625
1987	476.1904761904762
1988	393.1168831168831
1989	428.57142857142856
1990	438.4615384615385
1991	505.4545454545455
1992	490.76923076923083
1993	816.25
1994	809.6969696969697
1995	827.8787878787879
1996	846.0606060606061
1997	770.8108108108108
1998	576.8932038834952
1999	545.9706959706959
2000	501.1725293132328
2001	462.55778120184897
2002	444.5588235294117
2003	501.4705882352941
2004	562.2743682310469
2005	624.7035573122529
2006	732.1917808219177
2007	882.1138211382113