Year	Percent
1950	16.24263
1955	17.40232
1960	18.24538
1965	17.68684
1970	15.3237
1975	13.26743
1980	14.5553
1985	15.12563
1990	15.39576
1995	14.57324
2000	13.76355
2005	11.2136
2010	13.13199
2015	12.67764
2020	12.16027
2025	11.43832
2030	10.59259
2035	9.9716
2040	9.8217
2045	9.83013
2050	9.56974
2055	9.07565
2060	8.51732
2065	8.07587
2070	7.8336
2075	7.70325
2080	7.52819
2085	7.21705
2090	6.83546
2095	6.51162
2100	6.30296
