Year	Percent
1950	28.50166
1955	27.56687
1960	25.76829
1965	24.71175
1970	22.50841
1975	23.70916
1980	25.64788
1985	28.15953
1990	30.57933
1995	31.17466
2000	32.22924
2005	32.78813
2010	33.7503
2015	33.01411
2020	31.3565
2025	28.79251
2030	26.81337
2035	26.96125
2040	27.664
2045	28.12169
2050	27.54852
2055	25.58193
2060	24.04723
2065	23.38663
2070	23.43943
2075	23.638
2080	23.44474
2085	22.7998
2090	22.0534
2095	21.58734
2100	21.51073