Year	Percent
1950	13.418
1955	13.63277
1960	13.98702
1965	14.53711
1970	14.82331
1975	14.87407
1980	13.64187
1985	11.91138
1990	10.34125
1995	9.17672
2000	8.3893
2005	7.41223
2010	6.58835
2015	6.32647
2020	5.83963
2025	5.18455
2030	4.87958
2035	4.84198
2040	4.80766
2045	4.71503
2050	4.62489
2055	4.54111
2060	4.48946
2065	4.50315
2070	4.56219
2075	4.60155
2080	4.61193
2085	4.60365
2090	4.61099
2095	4.63997
2100	4.6864