Year	Percent
1950	16.5396
1955	16.55851
1960	16.76131
1965	16.87051
1970	17.22268
1975	17.39627
1980	18.10093
1985	18.37789
1990	18.15595
1995	18.06734
2000	18.08433
2005	17.96724
2010	17.77318
2015	17.08672
2020	16.30836
2025	15.58132
2030	14.92302
2035	14.24802
2040	13.53443
2045	12.79265
2050	12.06892
2055	11.42137
2060	10.81184
2065	10.26634
2070	9.75095
2075	9.24977
2080	8.77837
2085	8.34286
2090	7.92589
2095	7.55676
2100	7.22143