Year	Percent
1950	32.88165
1955	31.97286
1960	34.51168
1965	31.48738
1970	29.14952
1975	30.11071
1980	29.9804
1985	32.51829
1990	31.09821
1995	29.97266
2000	29.06644
2005	29.89116
2010	31.7521
2015	30.65094
2020	27.59062
2025	24.37394
2030	21.63081
2035	22.45317
2040	24.70745
2045	25.88716
2050	25.64216
2055	24.10347
2060	23.21418
2065	23.32762
2070	24.20428
2075	25.00177
2080	25.01448
2085	24.2909
2090	23.46178
2095	23.07787
2100	23.19666