Year	Number
1961	92.17032967032966
1962	91.80327868852459
1963	91.44021739130434
1964	91.08108108108108
1965	90.7258064516129
1966	90.37433155080214
1967	90.02659574468085
1968	89.68253968253968
1969	89.34210526315789
1970	87.13480266529984
1971	86.1589068825911
1972	85.20739630184909
1973	83.25207215992198
1974	82.36994219653178
1975	82.61078998073218
1976	81.96045736064794
1977	84.004884004884
1978	86.15981963927855
1979	88.41604525584982
1980	89.62460896767466
1981	92.07072060005358
1982	95.99162011173185
1983	97.39229024943312
1984	98.84892086330936
1985	99.70963995354239
1986	113.05903398926655
1987	134.16775032509753
1988	122.42562929061785
1989	119.28338762214983
1990	127.58743754461099
1991	139.92551210428306
1992	163.52459016393445
1993	181.03298611111111
1994	181.51142355008787
1995	203.77830188679246
1996	222.99748110831231
1997	270.98890010090815
1998	271.5007579585649
1999	298.61111111111114
2000	307.25714285714287
2001	307.37142857142857
2002	326.1212121212121
2003	358.8666666666667
2004	359
2005	371.51724137931035
2006	399.18518518518516
2007	427.21870047543587