Year	Percent
1950	25.19192
1955	25.86045
1960	25.98067
1965	25.89223
1970	24.49174
1975	22.46089
1980	20.75471
1985	20.19039
1990	21.7824
1995	23.56863
2000	25.36598
2005	26.37242
2010	26.41993
2015	26.53117
2020	25.86861
2025	25.33476
2030	24.7475
2035	24.41703
2040	24.6707
2045	24.60266
2050	24.29938
2055	23.81585
2060	23.56406
2065	23.52979
2070	23.41206
2075	23.40468
2080	23.21774
2085	22.9494
2090	22.70484
2095	22.53222
2100	22.41354
