Year	Percent
1950	7.8955
1955	8.51574
1960	7.76483
1965	7.64611
1970	8.07934
1975	7.76543
1980	7.15288
1985	5.93319
1990	5.01084
1995	4.64365
2000	4.51655
2005	4.36705
2010	4.42304
2015	4.46638
2020	4.11752
2025	3.96086
2030	3.8999
2035	3.95027
2040	4.05697
2045	4.15342
2050	4.19291
2055	4.1896
2060	4.20451
2065	4.27255
2070	4.37185
2075	4.45398
2080	4.48996
2085	4.47818
2090	4.43858
2095	4.4102
2100	4.40236