Year	Percent
1950	18.95712
1955	20.3886
1960	19.6593
1965	18.42472
1970	17.62167
1975	16.97408
1980	15.02494
1985	15.05564
1990	16.47976
1995	20.1684
2000	23.99508
2005	27.25604
2010	28.16049
2015	28.24286
2020	26.89381
2025	25.55381
2030	24.52122
2035	23.60042
2040	23.18585
2045	22.89543
2050	22.95352
2055	22.97538
2060	23.06615
2065	22.93767
2070	22.79421
2075	22.61456
2080	22.4751
2085	22.38199
2090	22.32004
2095	22.2679
2100	22.19609