Year	Percent
1950	17.01744
1955	16.78033
1960	17.52658
1965	17.97479
1970	18.29154
1975	18.75117
1980	20.65422
1985	21.16073
1990	19.65256
1995	16.81876
2000	13.88001
2005	11.44114
2010	11.84416
2015	12.70067
2020	11.26859
2025	9.67335
2030	8.08871
2035	7.16051
2040	6.81486
2045	6.73079
2050	6.52808
2055	6.11278
2060	5.62036
2065	5.2429
2070	5.07496
2075	5.05594
2080	5.05758
2085	4.97823
2090	4.82408
2095	4.67382
2100	4.59712