Year	Percent
1950	18.7632
1955	18.26556
1960	18.4019
1965	18.55787
1970	18.62075
1975	18.60659
1980	18.59061
1985	18.67772
1990	18.69168
1995	18.8005
2000	18.65594
2005	18.88326
2010	19.0411
2015	18.73335
2020	17.87489
2025	16.98548
2030	16.17813
2035	15.35777
2040	14.48873
2045	13.56564
2050	12.67828
2055	11.86998
2060	11.12701
2065	10.47198
2070	9.82954
2075	9.23549
2080	8.69521
2085	8.19089
2090	7.75049
2095	7.35915
2100	7.01503