Year	Percent
1950	20.41666
1955	21.63024
1960	21.66574
1965	22.6955
1970	23.97951
1975	24.41977
1980	25.57043
1985	25.32027
1990	24.35856
1995	24.07027
2000	24.80746
2005	26.20412
2010	27.4404
2015	29.08227
2020	29.8512
2025	29.97665
2030	28.16213
2035	26.0527
2040	23.99955
2045	22.65051
2050	23.05835
2055	23.30342
2060	22.97918
2065	22.31279
2070	21.18861
2075	20.78618
2080	21.04554
2085	21.57115
2090	21.84502
2095	21.73013
2100	21.33158