Year	Percent
1950	21.82691
1955	23.79246
1960	22.99431
1965	23.46058
1970	23.41543
1975	23.35475
1980	25.29396
1985	25.12134
1990	25.78048
1995	26.25464
2000	26.80771
2005	28.60342
2010	29.81008
2015	31.28717
2020	31.12713
2025	29.17596
2030	26.64448
2035	24.30196
2040	23.07031
2045	22.9504
2050	23.36428
2055	23.51512
2060	23.53697
2065	23.25709
2070	22.78356
2075	22.69509
2080	22.79046
2085	22.91509
2090	22.89908
2095	22.70317
2100	22.421