Year	Percent
1950	15.54567
1955	15.71791
1960	16.36855
1965	15.81954
1970	15.45144
1975	15.0499
1980	13.63711
1985	13.65637
1990	13.94471
1995	13.59049
2000	12.7942
2005	12.07766
2010	10.66894
2015	10.0862
2020	9.46109
2025	9.1287
2030	8.65426
2035	8.09828
2040	7.57198
2045	7.15392
2050	6.81066
2055	6.52715
2060	6.26255
2065	6.00907
2070	5.78516
2075	5.6134
2080	5.46594
2085	5.32803
2090	5.21184
2095	5.12076
2100	5.04752
