Year	Percent
1950	29.93971
1955	31.42656
1960	32.03847
1965	30.91149
1970	27.54754
1975	26.56728
1980	27.35595
1985	28.89379
1990	29.77936
1995	31.58142
2000	32.11098
2005	31.4392
2010	29.40814
2015	26.31677
2020	23.90738
2025	22.17977
2030	22.29078
2035	22.14589
2040	21.41829
2045	20.44438
2050	19.13741
2055	18.68932
2060	19.04247
2065	19.75129
2070	20.25545
2075	20.33134
2080	20.06473
2085	19.77257
2090	19.75022
2095	20.01867
2100	20.35085