Year	Percent
1950	29.18546
1955	28.84136
1960	28.19487
1965	27.91569
1970	27.55591
1975	28.17395
1980	28.26006
1985	27.41407
1990	27.48298
1995	27.45414
2000	29.81852
2005	33.00494
2010	35.12518
2015	36.49626
2020	37.91208
2025	38.2654
2030	37.65271
2035	36.08528
2040	34.73062
2045	34.02065
2050	33.26644
2055	32.6346
2060	31.97283
2065	31.32412
2070	30.71302
2075	30.14111
2080	29.57717
2085	28.95804
2090	28.30159
2095	27.60564
2100	26.90702