Year	Percent
1950	29.33764
1955	29.10895
1960	28.8029
1965	28.40803
1970	27.99056
1975	27.36849
1980	26.62715
1985	26.10744
1990	26.096
1995	26.75468
2000	27.58676
2005	28.42309
2010	28.9393
2015	29.40482
2020	30.14503
2025	31.06087
2030	32.19227
2035	32.91083
2040	33.19536
2045	33.11474
2050	32.7311
2055	32.35401
2060	31.91437
2065	31.3943
2070	30.80163
2075	30.19638
2080	29.58664
2085	28.99577
2090	28.41522
2095	27.84131
2100	27.29713