Year	Percent
1950	28.94415
1955	27.99078
1960	27.03263
1965	27.06903
1970	27.31343
1975	29.04146
1980	31.1714
1985	32.72048
1990	33.75675
1995	33.23711
2000	32.1172
2005	31.17492
2010	30.69814
2015	30.48478
2020	30.0398
2025	28.93351
2030	27.33787
2035	25.78757
2040	24.67931
2045	23.91285
2050	23.19488
2055	22.6328
2060	22.0999
2065	21.63148
2070	21.25814
2075	21.00638
2080	20.84482
2085	20.7213
2090	20.60102
2095	20.47669
2100	20.35637