Year	Percent
1950	9.19875
1955	7.88529
1960	8.32723
1965	9.31627
1970	8.82208
1975	7.34995
1980	6.34468
1985	6.69848
1990	7.03676
1995	6.93071
2000	6.33871
2005	5.99327
2010	6.42122
2015	6.42222
2020	6.26052
2025	6.02217
2030	5.71303
2035	5.54464
2040	5.56576
2045	5.63236
2050	5.61511
2055	5.51525
2060	5.38823
2065	5.29541
2070	5.26671
2075	5.26857
2080	5.25273
2085	5.19721
2090	5.11332
2095	5.03299
2100	4.98224