Year	Percent
1950	4.28009
1955	4.13279
1960	4.02108
1965	3.93983
1970	3.84042
1975	3.82471
1980	3.86457
1985	4.00503
1990	4.48663
1995	4.85935
2000	5.14109
2005	5.49122
2010	5.96291
2015	6.62729
2020	7.6715
2025	8.86549
2030	10.60549
2035	12.57051
2040	15.04871
2045	18.11122
2050	21.99117
2055	25.45868
2060	28.26938
2065	30.45429
2070	32.43642
2075	33.98747
2080	35.38383
2085	36.42644
2090	37.08573
2095	37.46379
2100	37.70346