Year	Percent
1950	12.37201
1955	12.11004
1960	12.02659
1965	12.08141
1970	12.87903
1975	14.25427
1980	14.89345
1985	15.63383
1990	17.70909
1995	19.47164
2000	22.45458
2005	26.00079
2010	27.48045
2015	27.71776
2020	28.38744
2025	27.30729
2030	27.05298
2035	28.40483
2040	28.25308
2045	29.41062
2050	29.52351
2055	27.62217
2060	26.08859
2065	24.43871
2070	23.96245
2075	24.31831
2080	24.56406
2085	24.38439
2090	23.85833
2095	23.38755
2100	23.22934