Year	Percent
1950	29.44332
1955	28.86912
1960	30.07537
1965	26.38835
1970	23.34208
1975	23.42386
1980	25.25475
1985	29.38221
1990	30.13749
1995	30.32129
2000	30.39019
2005	31.43743
2010	32.28758
2015	32.52895
2020	31.51746
2025	29.2856
2030	27.08381
2035	27.71672
2040	28.80374
2045	29.81769
2050	29.13704
2055	27.15016
2060	26.11179
2065	25.92379
2070	26.06808
2075	25.90595
2080	25.25365
2085	24.36733
2090	23.59277
2095	23.11986
2100	22.89415