Year	Percent
1950	31.65382
1955	31.61468
1960	30.21951
1965	28.52297
1970	26.93727
1975	25.74467
1980	26.53072
1985	28.01951
1990	29.27656
1995	30.82176
2000	31.41149
2005	30.68949
2010	28.47683
2015	24.44173
2020	20.90484
2025	19.57574
2030	19.92609
2035	20.13154
2040	20.1919
2045	19.50058
2050	18.3588
2055	17.91661
2060	18.06876
2065	18.67004
2070	19.31605
2075	19.65063
2080	19.55097
2085	19.17767
2090	18.86941
2095	18.80036
2100	18.90625