Year	Number
1961	640.1869158878504
1962	693.2084309133489
1963	737.0892018779343
1964	808.8117647058823
1965	849.0566037735849
1966	887.7068557919621
1967	939.5017793594307
1968	973.8406658739596
1969	1080.8121212121214
1970	1108.5344827586207
1971	1168.7562189054727
1972	1206.0277427490541
1973	1269.9492385786803
1974	1291.5802781289508
1975	1325.9746835443036
1976	1387.124842370744
1977	1438.7844611528822
1978	1506.8407960199006
1979	1572.487922705314
1980	1603.6809815950921
1981	1647.2727272727273
1982	1661.1694510739856
1983	1707.3167848699763
1984	1711.830985915493
1985	1756.440281030445
1986	1782.7630057803467
1987	1741.0982658959535
1988	1759.689655172414
1989	1761.9134396355353
1990	1779.0697674418607
1991	1708.0045095828636
1992	1708.4282460136674
1993	1683.6158192090395
1994	1652.9464285714287
1995	1479.2299898682877
1996	1437.1859296482412
1997	1560.758082497213
1998	1525.6124721603564
1999	1523.1519274376417
2000	1525.1877133105802
2001	1518.5698070374574
2002	1520.5922551252847
2003	1529.6096440872561
2004	1529.9309551208285
2005	1539.1299303944315