Year	Percent
1950	16.51513
1955	15.69337
1960	15.71815
1965	15.75057
1970	16.21856
1975	16.00482
1980	16.9055
1985	17.79233
1990	18.57677
1995	21.06889
2000	23.14615
2005	26.54928
2010	29.10022
2015	30.46202
2020	29.41474
2025	26.01685
2030	21.72872
2035	19.49748
2040	20.07654
2045	21.53822
2050	23.5621
2055	23.4853
2060	22.00185
2065	20.97913
2070	20.92945
2075	21.24823
2080	21.78839
2085	21.76273
2090	21.05286
2095	20.26362
2100	19.92039