Year	Percent
1950	17.10826
1955	18.16771
1960	19.06892
1965	18.49318
1970	16.05187
1975	13.96015
1980	15.39672
1985	16.15958
1990	16.64805
1995	15.80614
2000	14.61233
2005	12.22686
2010	14.06717
2015	13.58009
2020	12.90296
2025	12.05063
2030	11.18734
2035	10.56277
2040	10.43424
2045	10.4695
2050	10.21359
2055	9.71123
2060	9.14718
2065	8.70731
2070	8.48042
2075	8.37237
2080	8.21074
2085	7.89718
2090	7.50301
2095	7.16222
2100	6.93765