Year	Percent
1950	32.70225
1955	33.09342
1960	33.2835
1965	33.14153
1970	29.04553
1975	34.35434
1980	44.35539
1985	45.11459
1990	46.00324
1995	45.19894
2000	41.67078
2005	46.17303
2010	51.03294
2015	48.84211
2020	53.1168
2025	46.38792
2030	42.78019
2035	41.04693
2040	39.45917
2045	38.59237
2050	34.98897
2055	31.12601
2060	27.9428
2065	26.10296
2070	25.02058
2075	24.0212
2080	23.37981
2085	23.06217
2090	22.90988
2095	22.78617
2100	22.62799