Year	Percent
1950	29.87225
1955	26.72811
1960	25.13077
1965	26.04037
1970	27.70354
1975	31.14387
1980	33.38227
1985	36.63824
1990	34.89351
1995	35.48566
2000	31.12414
2005	27.73994
2010	24.10399
2015	24.47124
2020	25.84397
2025	27.48549
2030	28.61367
2035	26.74115
2040	25.13152
2045	24.26838
2050	24.10887
2055	24.87483
2060	25.07108
2065	24.54427
2070	23.55575
2075	22.74013
2080	22.46413
2085	22.59406
2090	22.75016
2095	22.61634
2100	22.22822