Year	Percent
1950	13.26944
1955	12.99181
1960	12.97454
1965	12.80966
1970	12.80419
1975	12.96641
1980	13.12471
1985	13.45633
1990	14.03978
1995	15.04274
2000	16.58758
2005	18.68864
2010	20.34157
2015	21.29379
2020	22.09025
2025	22.57816
2030	23.46102
2035	24.41873
2040	24.9857
2045	25.35518
2050	25.48377
2055	25.72325
2060	25.96045
2065	26.01891
2070	25.88644
2075	25.61266
2080	25.30197
2085	25.00479
2090	24.70188
2095	24.41292
2100	24.13421