Year	Percent
1950	18.90851
1955	18.28648
1960	18.40496
1965	18.30702
1970	16.73821
1975	16.50098
1980	16.53698
1985	16.63416
1990	16.31635
1995	15.70379
2000	15.42282
2005	14.30792
2010	14.70951
2015	13.40676
2020	12.67133
2025	11.92396
2030	11.28895
2035	10.75537
2040	10.26425
2045	9.79224
2050	9.32699
2055	8.85821
2060	8.43381
2065	8.03729
2070	7.68163
2075	7.33267
2080	7.00471
2085	6.70251
2090	6.43589
2095	6.19473
2100	5.98267