Year	per person
1800	1.403
1820	1.433
1913	3.194
1950	6.259
1973	9.705
1990	10.15
1991	9.932
1992	7.578
1993	5.762
1994	4.581
1995	4.01
1996	4.042
1997	4.262
1998	4.676
1999	5.012
2000	5.555
2001	6.087
2002	6.709
2003	7.429
2004	8.246
2005	10.19
2006	13.56
2007	16.77
2008	18.38
2009	19.93