Year	Percent
1950	9.48887
1955	9.33164
1960	9.91151
1965	9.95575
1970	9.52974
1975	9.24542
1980	8.41692
1985	6.57684
1990	5.36325
1995	4.89471
2000	4.62408
2005	4.97822
2010	5.27162
2015	4.67583
2020	4.26754
2025	3.94295
2030	3.82869
2035	3.91368
2040	4.08431
2045	4.19011
2050	4.14568
2055	4.04697
2060	4.01419
2065	4.08277
2070	4.22554
2075	4.37024
2080	4.43484
2085	4.40654
2090	4.33277
2095	4.28521
2100	4.28372