Year	Percent
1950	13.14959
1955	13.13239
1960	14.6663
1965	15.81548
1970	13.45368
1975	10.3397
1980	9.11582
1985	7.41264
1990	6.79589
1995	6.89141
2000	7.47278
2005	6.36892
2010	5.51689
2015	4.94374
2020	4.54636
2025	4.24583
2030	4.01739
2035	3.89628
2040	3.73508
2045	3.57513
2050	3.46302
2055	3.40968
2060	3.39768
2065	3.40602
2070	3.40633
2075	3.39062
2080	3.36502
2085	3.35173
2090	3.34185
2095	3.34141
2100	3.3375