Year	Percent
1950	18.00446
1955	17.43436
1960	17.33991
1965	17.84412
1970	17.96364
1975	18.3633
1980	18.75114
1985	18.65866
1990	18.7019
1995	18.2406
2000	18.37956
2005	17.31699
2010	15.64614
2015	14.67948
2020	13.73136
2025	12.76142
2030	11.75883
2035	10.83895
2040	9.99107
2045	9.26882
2050	8.61038
2055	8.00899
2060	7.46401
2065	6.98832
2070	6.57444
2075	6.22992
2080	5.93606
2085	5.69552
2090	5.48638
2095	5.31568
2100	5.16985