Year	Percent
1950	17.16301
1955	19.35754
1960	19.37449
1965	17.82989
1970	16.91015
1975	16.05569
1980	13.90357
1985	13.66176
1990	12.30299
1995	13.55771
2000	13.07698
2005	11.35445
2010	10.24332
2015	9.94859
2020	9.58009
2025	9.01335
2030	8.4
2035	7.83827
2040	7.37711
2045	7.02994
2050	6.73246
2055	6.44941
2060	6.171
2065	5.93319
2070	5.74014
2075	5.59737
2080	5.49103
2085	5.39932
2090	5.30675
2095	5.22256
2100	5.15496
