Year	Percent
1950	19.93463
1955	19.38014
1960	18.03795
1965	16.91076
1970	16.17506
1975	15.75235
1980	14.92832
1985	13.6448
1990	12.92356
1995	13.74537
2000	16.40936
2005	19.7942
2010	22.84184
2015	24.53997
2020	25.42579
2025	26.36456
2030	27.6104
2035	28.44851
2040	27.30442
2045	25.39171
2050	23.5532
2055	22.24372
2060	22.60495
2065	23.35006
2070	23.38662
2075	22.75446
2080	22.124
2085	21.68981
2090	21.74875
2095	22.08875
2100	22.21077