Year	Percent
1950	6.75776
1955	6.73895
1960	6.89398
1965	6.75606
1970	6.10041
1975	6.56117
1980	6.17848
1985	6.78336
1990	7.03404
1995	5.16806
2000	3.63346
2005	4.03186
2010	4.80673
2015	4.54151
2020	4.44515
2025	4.27299
2030	3.98923
2035	3.91939
2040	4.21069
2045	4.54352
2050	4.64741
2055	4.56098
2060	4.42913
2065	4.37964
2070	4.49076
2075	4.68876
2080	4.83045
2085	4.82309
2090	4.70776
2095	4.60025
2100	4.57622