Year	Percent
1950	18.35676
1955	17.58513
1960	17.49763
1965	18.02131
1970	18.15754
1975	18.56621
1980	18.96989
1985	18.87581
1990	18.92745
1995	18.48148
2000	18.65102
2005	17.5753
2010	15.88803
2015	14.92001
2020	13.95534
2025	12.98642
2030	11.97996
2035	11.05249
2040	10.19723
2045	9.46581
2050	8.80192
2055	8.19704
2060	7.6496
2065	7.17204
2070	6.75498
2075	6.40793
2080	6.1108
2085	5.86585
2090	5.65031
2095	5.47195
2100	5.31721