Year	Percent
1950	17.96384
1955	18.34162
1960	18.92835
1965	20.73527
1970	20.76815
1975	20.01686
1980	19.76352
1985	19.14813
1990	19.45555
1995	19.79961
2000	17.99705
2005	15.96992
2010	15.32339
2015	14.87055
2020	14.19943
2025	13.26621
2030	12.29574
2035	11.45588
2040	10.78784
2045	10.23004
2050	9.69171
2055	9.14151
2060	8.59195
2065	8.10329
2070	7.66946
2075	7.29738
2080	6.95683
2085	6.63932
2090	6.34828
2095	6.07576
2100	5.84408