Year	Percent
1950	4.44768
1955	4.11179
1960	3.97736
1965	3.96606
1970	3.98172
1975	4.01037
1980	4.04017
1985	4.06312
1990	4.30372
1995	4.19821
2000	3.81506
2005	3.6015
2010	3.42974
2015	3.34808
2020	3.30554
2025	3.37408
2030	3.62996
2035	4.05146
2040	4.5795
2045	5.17099
2050	5.83924
2055	6.63863
2060	7.56341
2065	8.66283
2070	9.89015
2075	11.19814
2080	12.57752
2085	14.01605
2090	15.49876
2095	16.99636
2100	18.48157