Year	Percent
1950	3.93846
1955	4.29636
1960	4.96724
1965	5.60148
1970	5.87072
1975	5.74839
1980	5.45056
1985	5.10354
1990	5.20844
1995	4.96435
2000	4.80318
2005	4.69305
2010	4.34761
2015	4.53212
2020	4.40205
2025	4.51123
2030	5.16908
2035	5.96369
2040	6.77812
2045	7.50867
2050	8.2105
2055	8.89061
2060	9.62546
2065	10.3269
2070	11.1843
2075	12.21137
2080	13.26365
2085	14.32709
2090	15.43039
2095	16.60394
2100	17.83785