Year	Percent
1950	21.3312
1955	22.07259
1960	21.78457
1965	22.02569
1970	22.59869
1975	23.13717
1980	22.9959
1985	22.65769
1990	22.56145
1995	22.70905
2000	24.76645
2005	26.82969
2010	28.52984
2015	30.95699
2020	32.33643
2025	31.40047
2030	29.00579
2035	25.75338
2040	22.49553
2045	21.49106
2050	22.20738
2055	22.86244
2060	23.42111
2065	23.12081
2070	22.13014
2075	21.70394
2080	21.71264
2085	22.04158
2090	22.33837
2095	22.34416
2100	22.04314