Year	Percent
1950	18.05022
1955	16.41411
1960	17.2079
1965	17.84712
1970	18.24576
1975	18.43819
1980	18.19778
1985	17.6723
1990	17.47716
1995	16.2597
2000	13.67479
2005	11.57009
2010	10.57331
2015	9.42528
2020	8.79213
2025	7.94642
2030	7.11268
2035	6.42588
2040	5.95007
2045	5.64412
2050	5.42021
2055	5.203
2060	4.97958
2065	4.78559
2070	4.66006
2075	4.60695
2080	4.5946
2085	4.58798
2090	4.56701
2095	4.54054
2100	4.53047