Year	Percent
1950	15.86487
1955	19.43972
1960	19.80046
1965	19.88088
1970	18.52359
1975	17.08228
1980	16.38989
1985	15.93685
1990	14.06168
1995	12.66708
2000	11.04686
2005	10.51542
2010	10.19914
2015	10.30401
2020	9.36594
2025	8.47723
2030	7.73535
2035	7.20765
2040	6.86826
2045	6.60752
2050	6.32007
2055	5.98683
2060	5.66294
2065	5.40529
2070	5.23389
2075	5.12419
2080	5.03245
2085	4.92578
2090	4.81452
2095	4.71899
2100	4.65595