Year	Percent
1950	30.61351
1955	29.92965
1960	29.1749
1965	28.17905
1970	27.52061
1975	28.2014
1980	28.90487
1985	29.71298
1990	30.39849
1995	30.55362
2000	30.84442
2005	31.47989
2010	32.11853
2015	32.58053
2020	32.75935
2025	32.47381
2030	31.88622
2035	30.86517
2040	29.86672
2045	28.8518
2050	27.91271
2055	27.28274
2060	26.51443
2065	25.71329
2070	24.97628
2075	24.38622
2080	23.95026
2085	23.59051
2090	23.23299
2095	22.88174
2100	22.56801