Year	Percent
1950	15.27472
1955	16.18307
1960	15.35736
1965	15.82981
1970	16.6526
1975	18.19147
1980	20.19029
1985	20.6541
1990	21.44855
1995	22.89255
2000	24.23818
2005	25.95997
2010	27.43079
2015	27.57129
2020	27.88919
2025	28.65909
2030	29.34857
2035	29.84394
2040	29.00055
2045	27.33585
2050	25.32474
2055	23.96932
2060	23.80257
2065	23.98885
2070	24.33605
2075	24.09605
2080	23.54973
2085	23.06596
2090	22.90122
2095	23.02831
2100	23.17194