Year	Percent
1950	20.12013
1955	19.95788
1960	20.39835
1965	19.05019
1970	17.42541
1975	16.28871
1980	16.13838
1985	16.6337
1990	16.41505
1995	18.75983
2000	19.39999
2005	19.54314
2010	19.98967
2015	21.05467
2020	21.57233
2025	21.22688
2030	20.16165
2035	19.65814
2040	19.89939
2045	20.89553
2050	22.25206
2055	22.96515
2060	23.09851
2065	22.97314
2070	22.81948
2075	22.8782
2080	23.0956
2085	23.26343
2090	23.26151
2095	23.1189
2100	22.93617