Year	Percent
1950	4.51111
1955	4.3174
1960	4.10854
1965	3.88071
1970	3.7542
1975	3.80633
1980	4.71642
1985	4.35092
1990	4.17752
1995	3.6208
2000	3.8234
2005	3.57748
2010	3.82323
2015	4.82064
2020	6.34866
2025	7.82965
2030	9.41938
2035	11.21737
2040	13.24519
2045	15.30949
2050	17.30137
2055	19.02963
2060	20.35549
2065	21.54221
2070	22.67317
2075	24.11354
2080	25.4657
2085	26.75012
2090	27.91378
2095	28.93869
2100	29.84962