Year	Percent
1950	17.82874
1955	17.97634
1960	18.07122
1965	18.53856
1970	19.10802
1975	19.57433
1980	19.63548
1985	19.63692
1990	18.98887
1995	16.94394
2000	14.81778
2005	14.31249
2010	14.0552
2015	13.51854
2020	12.86046
2025	11.87033
2030	10.93784
2035	10.22519
2040	9.6721
2045	9.12946
2050	8.55204
2055	7.98211
2060	7.4832
2065	7.0833
2070	6.76433
2075	6.48834
2080	6.24026
2085	6.00503
2090	5.81002
2095	5.65121
2100	5.52692