Year	Percent
1950	4.24169
1955	4.26348
1960	4.25878
1965	4.18368
1970	4.08416
1975	3.9784
1980	3.90275
1985	3.9049
1990	4.28234
1995	4.37172
2000	4.2808
2005	4.25661
2010	4.27509
2015	4.36463
2020	4.46994
2025	4.59657
2030	4.77995
2035	5.08713
2040	5.53127
2045	6.00199
2050	6.52642
2055	7.1725
2060	7.93277
2065	8.66201
2070	9.37304
2075	10.17347
2080	11.04474
2085	11.95598
2090	12.88409
2095	13.84828
2100	14.84719