Year	Percent
1950	12.14
1955	12.23605
1960	12.41861
1965	11.92471
1970	12.1601
1975	12.27106
1980	12.36696
1985	12.51716
1990	12.59781
1995	12.58344
2000	12.60794
2005	12.56165
2010	12.17209
2015	12.6568
2020	12.56097
2025	12.48796
2030	12.0954
2035	11.74648
2040	11.4772
2045	11.21722
2050	10.89963
2055	10.54277
2060	10.16064
2065	9.80492
2070	9.48078
2075	9.15542
2080	8.84663
2085	8.53641
2090	8.23308
2095	7.95061
2100	7.69309
