Year	Number
1961	212.1357487171513
1962	238.2907385697538
1963	267.1484929777497
1964	299.33878393395776
1965	335.31060364100927
1966	370.37367405978785
1967	411.03721042860604
1968	439.64927911874287
1969	478.04107683495624
1970	512.9439252336448
1971	691.0619282935548
1972	743.4025338017673
1973	799.7049956933678
1974	837.6456701362807
1975	878.171489817792
1976	924.5140965399403
1977	971.8773373223636
1978	1008.5673473706486
1979	1061.7138032925284
1980	1130.6211114626174
1981	1167.9621804352419
1982	1204.3243814759992
1983	1281.2368536371605
1984	1316.915466637353
1985	1355.9491712707181
1986	1396.81598062954
1987	1451.1053502482075
1988	1521.4690779191783
1989	1556.0713888580005
1990	1586.5024411895251
1991	1635.7426966292135
1992	1635.721142857143
1993	1712.6573099415205
1994	1789.8511225837435
1995	1838.0574671012919
1996	1849.7683629380704
1997	1891.873258209136
1998	1922.229559370873
1999	1895.943826799298
2000	1938.45146833353
2001	2033.8038134068831
2002	2117.052009170991