Year	Percent
1950	28.77129
1955	28.48624
1960	27.95543
1965	27.2162
1970	26.45426
1975	26.05689
1980	25.71589
1985	26.16387
1990	27.03154
1995	28.39138
2000	29.71799
2005	30.28311
2010	30.27068
2015	28.46078
2020	27.62285
2025	27.82546
2030	28.98427
2035	30.18512
2040	30.57183
2045	30.5209
2050	30.24253
2055	30.06223
2060	30.13092
2065	30.09019
2070	29.82142
2075	29.39611
2080	28.95907
2085	28.60953
2090	28.29287
2095	27.94658
2100	27.55135