Year	per Person
1970	2.1951
1971	2.35183
1972	2.59905
1973	2.72761
1974	2.59438
1975	2.62107
1976	2.58393
1977	2.68638
1978	2.55021
1979	2.75937
1980	2.59371
1981	2.47104
1982	2.52159
1983	2.34322
1984	2.51872
1985	2.68181
1986	2.46901
1987	2.65034
1988	3.03627
1989	3.17886
1990	3.21009
1991	3.37755
1992	3.69605
1993	4.03813
1994	4.30542
1995	4.54755
1996	4.66611
1997	4.70017
1998	4.78592
1999	4.79413
2000	4.91317
2001	4.97087
2002	4.94814
2003	4.73665
2004	4.7184
2005	4.75936
2006	4.73327
2007	4.5097
2008	4.29313
2009	3.93136
2010	3.80641
2011	3.7639
2012	3.63918
2013	3.60965
2014	3.71973
2015	3.73299
2016	3.76938