Year	Percent
1950	15.64776
1955	17.87335
1960	17.76098
1965	17.48435
1970	17.20053
1975	16.4255
1980	15.34926
1985	14.50348
1990	13.86905
1995	12.93653
2000	12.02995
2005	11.04888
2010	10.54191
2015	9.97458
2020	9.3258
2025	8.68481
2030	8.09761
2035	7.58351
2040	7.13122
2045	6.72597
2050	6.36409
2055	6.03934
2060	5.76006
2065	5.52268
2070	5.32177
2075	5.15785
2080	5.01708
2085	4.89849
2090	4.7986
2095	4.71652
2100	4.65524