Year	Percent
1950	31.5513
1955	30.14305
1960	27.27818
1965	24.17024
1970	22.44694
1975	23.53971
1980	25.99381
1985	29.24481
1990	31.85043
1995	32.80128
2000	33.6927
2005	34.68802
2010	35.42657
2015	35.47859
2020	33.30625
2025	30.43116
2030	28.11691
2035	26.59878
2040	26.78122
2045	27.14783
2050	26.36808
2055	24.83652
2060	23.57365
2065	22.77684
2070	22.71921
2075	23.0111
2080	23.12795
2085	22.86658
2090	22.41467
2095	22.06551
2100	21.9713