Year	Percent
1950	17.40797
1955	19.19081
1960	19.14974
1965	18.91447
1970	18.98233
1975	18.56211
1980	18.39645
1985	17.76961
1990	16.88828
1995	16.18637
2000	15.00004
2005	13.62604
2010	11.91656
2015	10.4116
2020	9.73298
2025	9.06008
2030	8.35095
2035	7.6358
2040	7.00731
2045	6.49852
2050	6.08775
2055	5.76624
2060	5.49206
2065	5.26452
2070	5.05099
2075	4.88858
2080	4.76752
2085	4.68734
2090	4.62967
2095	4.58556
2100	4.54155