Year	Percent
1950	27.98634
1955	26.33109
1960	24.79543
1965	23.76509
1970	23.11819
1975	25.65936
1980	27.87235
1985	30.68111
1990	33.38625
1995	32.77157
2000	32.80495
2005	29.35844
2010	28.87874
2015	29.61325
2020	30.60502
2025	31.53691
2030	32.52713
2035	31.09723
2040	29.7069
2045	28.91129
2050	28.70888
2055	28.11268
2060	27.23169
2065	26.36927
2070	25.65527
2075	25.11588
2080	24.68122
2085	24.26938
2090	23.84872
2095	23.44677
2100	23.11984