Year	per person
1800	1.008
1820	1.008
1870	0.9667
1913	1.391
1950	1.259
1951	1.294
1952	1.327
1953	1.362
1954	1.4
1955	1.435
1956	1.46
1957	1.483
1958	1.501
1959	1.514
1960	1.528
1961	1.553
1962	1.693
1963	1.688
1964	1.713
1965	1.677
1966	1.643
1967	1.397
1968	1.337
1969	1.414
1970	1.406
1971	1.442
1972	1.534
1973	1.599
1974	1.498
1975	1.358
1976	1.548
1977	1.565
1978	1.541
1979	1.521
1980	1.448
1981	1.467
1982	1.551
1983	1.6
1984	1.704
1985	1.766
1986	1.776
1987	1.8
1988	1.867
1989	1.905
1990	1.96
1991	2.033
1992	2.169
1993	2.301
1994	2.46
1995	2.649
1996	2.852
1997	3.039
1998	3.171
1999	3.28
2000	3.459
2001	3.655
2002	3.869
2003	4.106
2004	4.379
2005	4.697
2006	5.02
2007	5.381
2008	5.646
2009	5.876