Year	Percent
1950	29.01692
1955	28.07837
1960	27.08474
1965	27.00738
1970	27.1085
1975	28.67784
1980	30.66529
1985	32.13993
1990	33.17331
1995	32.68265
2000	31.58863
2005	30.60634
2010	30.03095
2015	29.70918
2020	29.18849
2025	28.05785
2030	26.47313
2035	24.97242
2040	23.92039
2045	23.2052
2050	22.5292
2055	22.00142
2060	21.49953
2065	21.06058
2070	20.71228
2075	20.47801
2080	20.32813
2085	20.21485
2090	20.10938
2095	20.00215
2100	19.89725