Year	Percent
1950	9.3127
1955	9.17641
1960	9.60447
1965	9.04708
1970	8.95842
1975	8.89124
1980	9.52209
1985	10.62739
1990	11.34085
1995	11.56278
2000	11.3215
2005	10.96053
2010	9.71728
2015	8.70464
2020	8.46789
2025	8.57928
2030	8.67491
2035	7.89091
2040	7.17335
2045	6.58166
2050	6.2734
2055	6.23928
2060	6.30047
2065	6.25043
2070	6.0469
2075	5.79143
2080	5.61829
2085	5.56081
2090	5.57477
2095	5.5774
2100	5.51921
