Year	Percent
1950	3.30004
1955	3.39221
1960	3.46844
1965	3.53112
1970	3.58548
1975	3.63352
1980	3.67619
1985	3.71193
1990	3.97084
1995	3.99621
2000	4.0327
2005	4.35906
2010	4.39739
2015	4.22764
2020	4.26756
2025	4.39556
2030	4.67198
2035	5.09505
2040	5.59468
2045	6.10629
2050	6.63437
2055	7.23703
2060	7.95509
2065	8.81802
2070	9.85888
2075	10.99865
2080	12.11648
2085	13.24197
2090	14.40011
2095	15.59274
2100	16.80297