Year	Percent
1950	15.73563
1955	16.9783
1960	16.93405
1965	17.04062
1970	17.3937
1975	17.8445
1980	18.15319
1985	18.35452
1990	18.66347
1995	18.79759
2000	18.87638
2005	19.27236
2010	19.4463
2015	18.74378
2020	17.80267
2025	17.07394
2030	16.38567
2035	15.58031
2040	14.66586
2045	13.71772
2050	12.81882
2055	12.02052
2060	11.28427
2065	10.62631
2070	9.99901
2075	9.40579
2080	8.87227
2085	8.37558
2090	7.94042
2095	7.56019
2100	7.21526