Year	Percent
1950	6.91062
1955	7.24844
1960	7.5425
1965	7.23684
1970	6.85826
1975	7.49278
1980	7.13038
1985	5.88156
1990	5.18017
1995	5.26915
2000	5.96537
2005	5.65997
2010	5.23057
2015	4.95487
2020	4.86281
2025	4.70306
2030	4.59112
2035	4.54785
2040	4.53222
2045	4.52292
2050	4.51465
2055	4.51587
2060	4.53434
2065	4.55838
2070	4.58809
2075	4.6081
2080	4.60735
2085	4.59679
2090	4.58399
2095	4.56856
2100	4.55639