Year	Percent
1950	4.04594
1955	3.75438
1960	3.70658
1965	3.69386
1970	3.76245
1975	3.80045
1980	3.78248
1985	3.72068
1990	3.8892
1995	3.78776
2000	3.65127
2005	3.50117
2010	3.35278
2015	3.20223
2020	3.15537
2025	3.28628
2030	3.6091
2035	4.1593
2040	4.82357
2045	5.48355
2050	6.14256
2055	6.83282
2060	7.64063
2065	8.54146
2070	9.41759
2075	10.29168
2080	11.22039
2085	12.20194
2090	13.21502
2095	14.23817
2100	15.26615