Year	Percent
1950	29.81422
1955	28.61883
1960	29.47672
1965	28.81757
1970	28.78999
1975	30.28034
1980	31.01044
1985	30.03009
1990	29.47083
1995	28.80062
2000	30.28073
2005	31.61311
2010	30.69464
2015	29.49273
2020	26.77898
2025	25.6779
2030	24.86593
2035	23.41993
2040	23.13989
2045	23.01706
2050	22.71756
2055	22.58213
2060	22.39848
2065	22.24989
2070	22.13295
2075	22.11426
2080	22.1272
2085	22.08594
2090	21.99254
2095	21.86019
2100	21.71424