Year	Percent
1950	10.24612
1955	9.64425
1960	9.98037
1965	11.01117
1970	8.90109
1975	7.15004
1980	7.01058
1985	7.39431
1990	8.10371
1995	6.83194
2000	5.96919
2005	5.2679
2010	4.76329
2015	4.67255
2020	4.49993
2025	4.49322
2030	4.46205
2035	4.36623
2040	4.29509
2045	4.29064
2050	4.34023
2055	4.40625
2060	4.46518
2065	4.50765
2070	4.53222
2075	4.55401
2080	4.58867
2085	4.62538
2090	4.64739
2095	4.65676
2100	4.64008
