Year	Percent
1950	18.32025
1955	19.90786
1960	19.1567
1965	17.48723
1970	16.6306
1975	16.99937
1980	15.88363
1985	15.47534
1990	17.12204
1995	22.56827
2000	29.14431
2005	32.79316
2010	32.40223
2015	30.407
2020	27.71779
2025	27.90402
2030	30.26204
2035	31.01756
2040	30.44084
2045	26.63058
2050	22.96537
2055	21.59327
2060	22.26251
2065	24.00361
2070	25.03138
2075	24.72452
2080	23.68868
2085	22.85548
2090	22.58675
2095	22.80985
2100	23.10346