Year	Percent
1950	12.45476
1955	12.82484
1960	11.76621
1965	10.50178
1970	11.46632
1975	12.00818
1980	13.43919
1985	13.82339
1990	13.43127
1995	12.84317
2000	11.94414
2005	11.5105
2010	11.28292
2015	10.91585
2020	10.78201
2025	10.53914
2030	9.74794
2035	9.09731
2040	8.56609
2045	8.1877
2050	7.89649
2055	7.56542
2060	7.1728
2065	6.75769
2070	6.42324
2075	6.16507
2080	5.97307
2085	5.7941
2090	5.60585
2095	5.42113
2100	5.27009
