Year	Percent
1950	16.46103
1955	16.19539
1960	17.59403
1965	18.33017
1970	18.44434
1975	17.35809
1980	17.51784
1985	16.87098
1990	15.50205
1995	13.99108
2000	12.77845
2005	11.67423
2010	10.40841
2015	9.46267
2020	8.74195
2025	7.98369
2030	7.27962
2035	6.64852
2040	6.13342
2045	5.75089
2050	5.44225
2055	5.1836
2060	4.97094
2065	4.79744
2070	4.66791
2075	4.56823
2080	4.49854
2085	4.45337
2090	4.42268
2095	4.40832
2100	4.4054