Year	Percent
1950	15.04162
1955	16.69924
1960	15.84485
1965	15.54902
1970	15.75747
1975	16.33631
1980	17.80924
1985	18.65066
1990	17.99808
1995	17.3313
2000	16.77282
2005	16.04098
2010	16.06956
2015	15.79391
2020	14.96039
2025	14.02051
2030	13.17231
2035	12.53961
2040	12.01665
2045	11.47527
2050	10.89748
2055	10.30097
2060	9.76491
2065	9.3173
2070	8.90642
2075	8.52383
2080	8.12217
2085	7.73391
2090	7.37355
2095	7.06351
2100	6.793
