Year	Percent
1950	18.38256
1955	16.58607
1960	13.87909
1965	13.79554
1970	13.1304
1975	12.52016
1980	12.31177
1985	12.45601
1990	12.27444
1995	11.87996
2000	12.18191
2005	13.03955
2010	13.48319
2015	14.93617
2020	16.1183
2025	16.65588
2030	16.90101
2035	17.27839
2040	18.28657
2045	19.81181
2050	21.64783
2055	22.87473
2060	23.34982
2065	23.513
2070	23.48152
2075	23.5959
2080	23.94619
2085	24.31207
2090	24.52151
2095	24.56802
2100	24.51633