Year	Percent
1950	28.24619
1955	26.7834
1960	25.18442
1965	23.88729
1970	23.25171
1975	25.68738
1980	27.86592
1985	30.80973
1990	33.66855
1995	33.44139
2000	33.38763
2005	29.67871
2010	29.38439
2015	29.9116
2020	30.31968
2025	30.64498
2030	31.35844
2035	29.98652
2040	28.76943
2045	28.13389
2050	28.00113
2055	27.43839
2060	26.55731
2065	25.67723
2070	24.91279
2075	24.29377
2080	23.78483
2085	23.31673
2090	22.858
2095	22.42961
2100	22.08334