Year	Percent
1950	12.29104
1955	12.74682
1960	13.46357
1965	11.88497
1970	12.01535
1975	13.53828
1980	13.72542
1985	13.38408
1990	13.30861
1995	12.80634
2000	13.25672
2005	14.15066
2010	13.28479
2015	11.93469
2020	11.62353
2025	11.51678
2030	11.26695
2035	10.77634
2040	10.19062
2045	9.66383
2050	9.2525
2055	8.91978
2060	8.59241
2065	8.23568
2070	7.85505
2075	7.50853
2080	7.19419
2085	6.92207
2090	6.66541
2095	6.41972
2100	6.19246
