Year	Percent
1950	10.11613
1955	10.25204
1960	11.26677
1965	9.14353
1970	7.36958
1975	7.06295
1980	7.37896
1985	8.00734
1990	6.63184
1995	5.78256
2000	5.07516
2005	4.55753
2010	4.40717
2015	4.21551
2020	4.17911
2025	4.12446
2030	4.01594
2035	3.93605
2040	3.927
2045	3.97652
2050	4.04216
2055	4.08946
2060	4.11549
2065	4.13414
2070	4.16731
2075	4.23001
2080	4.29133
2085	4.33298
2090	4.35512
2095	4.34797
2100	4.32954