Year	Percent
1950	15.03977
1955	18.8505
1960	19.19838
1965	18.64147
1970	17.41836
1975	16.13722
1980	15.56063
1985	15.22747
1990	13.38028
1995	11.95755
2000	10.30197
2005	9.73388
2010	9.42821
2015	9.56832
2020	8.72993
2025	7.91109
2030	7.22
2035	6.72469
2040	6.40664
2045	6.16934
2050	5.91575
2055	5.62645
2060	5.34855
2065	5.13322
2070	4.99489
2075	4.90864
2080	4.83278
2085	4.73657
2090	4.63206
2095	4.54058
2100	4.48002
