Year	Percent
1950	9.72399
1955	9.63052
1960	10.13564
1965	10.18304
1970	9.85007
1975	11.26639
1980	12.7942
1985	12.13827
1990	10.81093
1995	9.61493
2000	10.39956
2005	10.72115
2010	10.05149
2015	9.19343
2020	7.61428
2025	6.34201
2030	6.12625
2035	5.9497
2040	5.71312
2045	5.46153
2050	5.16614
2055	4.88476
2060	4.73576
2065	4.70931
2070	4.72217
2075	4.71567
2080	4.68387
2085	4.65067
2090	4.65744
2095	4.70461
2100	4.75439