Year	Percent
1950	15.89924
1955	15.92917
1960	16.42718
1965	17.83268
1970	16.43734
1975	15.61722
1980	15.15687
1985	14.0942
1990	12.76055
1995	10.36236
2000	8.49008
2005	7.68381
2010	7.84553
2015	8.7681
2020	8.08881
2025	7.16425
2030	6.30913
2035	5.81919
2040	5.7673
2045	5.87719
2050	5.84378
2055	5.59064
2060	5.25464
2065	5.03445
2070	4.99526
2075	5.0576
2080	5.09521
2085	5.03507
2090	4.89709
2095	4.77074
2100	4.71699