Year	Percent
1950	28.99258
1955	28.27899
1960	28.70934
1965	27.90497
1970	27.18357
1975	27.65313
1980	28.47106
1985	32.20853
1990	35.52287
1995	37.19804
2000	35.8105
2005	31.72998
2010	29.02396
2015	26.2484
2020	25.91405
2025	25.10182
2030	22.9452
2035	21.94881
2040	21.3069
2045	21.22494
2050	21.3161
2055	20.9316
2060	20.6148
2065	20.4397
2070	20.45963
2075	20.58032
2080	20.64979
2085	20.59605
2090	20.44339
2095	20.28202
2100	20.19966