Year	Percent
1950	16.58937
1955	16.59992
1960	16.22813
1965	16.11324
1970	16.27237
1975	16.56143
1980	16.96172
1985	16.94448
1990	17.30346
1995	16.96392
2000	14.63769
2005	12.74202
2010	12.14382
2015	11.30112
2020	10.41734
2025	9.48247
2030	8.6373
2035	7.91556
2040	7.29887
2045	6.76292
2050	6.29388
2055	5.89358
2060	5.56186
2065	5.30623
2070	5.10736
2075	4.946
2080	4.81665
2085	4.71571
2090	4.63818
2095	4.5821
2100	4.54857