Year	Percent
1950	27.36424
1955	28.23586
1960	31.19334
1965	31.69618
1970	32.14614
1975	32.34822
1980	31.78028
1985	32.7725
1990	33.15679
1995	31.26653
2000	31.53544
2005	31.03192
2010	30.22875
2015	27.74516
2020	24.39329
2025	21.55366
2030	20.36751
2035	20.76439
2040	21.53476
2045	22.11117
2050	21.65113
2055	20.87988
2060	20.55726
2065	20.90142
2070	21.65662
2075	22.27962
2080	22.35285
2085	21.92378
2090	21.40739
2095	21.17091
2100	21.26788