Year	Percent
1950	28.79738
1955	28.05913
1960	27.88091
1965	27.14409
1970	27.25032
1975	28.55193
1980	29.74342
1985	31.38649
1990	32.36728
1995	32.65557
2000	32.93645
2005	33.19722
2010	33.12474
2015	32.63216
2020	31.6684
2025	29.88547
2030	28.0281
2035	26.47377
2040	24.85227
2045	23.56844
2050	22.65918
2055	21.75679
2060	20.98407
2065	20.39709
2070	20.00565
2075	19.75402
2080	19.60136
2085	19.51212
2090	19.43911
2095	19.39341
2100	19.38084