Year	Percent
1950	12.49974
1955	12.65021
1960	12.61244
1965	12.55368
1970	12.92438
1975	13.25296
1980	12.90733
1985	12.6666
1990	12.7467
1995	13.00443
2000	12.37254
2005	12.10536
2010	11.64307
2015	10.74818
2020	11.28485
2025	10.48072
2030	10.08012
2035	9.62955
2040	9.24229
2045	8.92773
2050	8.62002
2055	8.32233
2060	8.023
2065	7.7099
2070	7.42316
2075	7.15208
2080	6.90851
2085	6.66296
2090	6.42983
2095	6.21424
2100	6.02615
