Year	Percent
1950	39.96458
1955	36.19939
1960	31.37515
1965	26.72551
1970	25.09282
1975	26.52603
1980	33.22877
1985	37.97616
1990	38.65614
1995	37.34585
2000	34.21354
2005	30.84768
2010	29.88307
2015	28.8396
2020	26.56033
2025	22.56949
2030	19.96491
2035	18.17828
2040	18.5105
2045	20.3082
2050	21.54154
2055	21.94896
2060	21.22431
2065	20.31302
2070	19.81108
2075	20.25093
2080	21.17595
2085	21.85341
2090	21.84927
2095	21.28421
2100	20.58022