Year	Percent
1950	18.20979
1955	17.16942
1960	18.29174
1965	17.96141
1970	15.70896
1975	13.21134
1980	13.2573
1985	13.3453
1990	12.74094
1995	11.35948
2000	9.84767
2005	8.3197
2010	7.7632
2015	7.12038
2020	6.5965
2025	6.06924
2030	5.63898
2035	5.29539
2040	5.02823
2045	4.84603
2050	4.69635
2055	4.56769
2060	4.45029
2065	4.36833
2070	4.3129
2075	4.28558
2080	4.27985
2085	4.27778
2090	4.27768
2095	4.27797
2100	4.28129