Year	Percent
1950	15.27496
1955	14.7933
1960	14.08022
1965	13.56129
1970	13.27253
1975	13.36846
1980	13.55057
1985	13.78772
1990	14.19413
1995	14.93379
2000	16.13505
2005	17.69087
2010	19.348
2015	20.67116
2020	22.09876
2025	23.14374
2030	24.24406
2035	25.1125
2040	25.2939
2045	25.35275
2050	25.17367
2055	25.20816
2060	25.39184
2065	25.42897
2070	25.23493
2075	24.75217
2080	24.30019
2085	23.94853
2090	23.67467
2095	23.41092
2100	23.12342