Year	Percent
1950	30.82961
1955	29.67954
1960	29.69788
1965	27.12079
1970	27.21522
1975	28.9246
1980	30.77663
1985	31.37154
1990	29.38338
1995	27.66629
2000	27.22574
2005	28.74613
2010	29.48713
2015	28.78224
2020	26.24481
2025	22.84903
2030	21.0659
2035	19.99244
2040	19.74481
2045	19.72983
2050	18.79224
2055	17.87184
2060	17.43918
2065	17.5707
2070	18.01124
2075	18.4942
2080	18.73162
2085	18.68815
2090	18.60747
2095	18.70617
2100	18.95992