Year	Percent
1950	30.32895
1955	28.38767
1960	28.57651
1965	25.24386
1970	22.6922
1975	24.04738
1980	26.12005
1985	29.88958
1990	31.27204
1995	31.13116
2000	31.49217
2005	31.7502
2010	33.47316
2015	33.89957
2020	32.10152
2025	30.41024
2030	28.50213
2035	28.67782
2040	29.85394
2045	30.21928
2050	29.83111
2055	27.98934
2060	26.90026
2065	26.65361
2070	26.75908
2075	26.56768
2080	25.85339
2085	24.90595
2090	24.15973
2095	23.81867
2100	23.72343