Year	per person
1800	0.9396
1820	0.9594
1913	2.139
1950	4.191
1973	10.18
1990	7.408
1991	6.594
1992	4.369
1993	3.604
1994	2.793
1995	2.408
1996	1.972
1997	1.97
1998	2.036
1999	2.07
2000	2.196
2001	2.37
2002	2.54
2003	2.741
2004	2.967
2005	3.099
2006	3.296
2007	3.532
2008	3.788
2009	3.893