Year	Percent
1950	18.73473
1955	18.47972
1960	19.17703
1965	19.79626
1970	19.72863
1975	19.93677
1980	19.73089
1985	19.08632
1990	18.71843
1995	18.593
2000	18.80954
2005	18.92861
2010	18.18438
2015	17.37163
2020	16.86416
2025	16.353
2030	15.74065
2035	15.05507
2040	14.37644
2045	13.77613
2050	13.22192
2055	12.70412
2060	12.15852
2065	11.64727
2070	11.16628
2075	10.72267
2080	10.30187
2085	9.88937
2090	9.49047
2095	9.1091
2100	8.74442