Year	per person
1800	1.353
1820	1.382
1913	3.08
1950	6.036
1973	9.359
1990	10.75
1991	8.812
1992	6.228
1993	6.137
1994	4.237
1995	4.182
1996	3.943
1997	4.014
1998	3.758
1999	3.633
2000	3.711
2001	3.936
2002	4.24
2003	4.503
2004	4.828
2005	5.18
2006	5.444
2007	5.621
2008	6.073
2009	5.687