Year	Percent
1950	29.67584
1955	27.34882
1960	25.65347
1965	26.73989
1970	28.85732
1975	32.10676
1980	33.95234
1985	36.91175
1990	35.12687
1995	34.99079
2000	31.12721
2005	27.95933
2010	24.22961
2015	23.93882
2020	24.635
2025	25.78527
2030	26.88134
2035	25.24548
2040	23.72307
2045	22.94923
2050	22.86224
2055	23.69314
2060	24.01708
2065	23.64031
2070	22.80083
2075	22.102
2080	21.88006
2085	22.04853
2090	22.23561
2095	22.14787
2100	21.79554