Year	Percent
1950	17.28746
1955	18.01503
1960	18.60548
1965	15.744
1970	15.66206
1975	11.9791
1980	12.89602
1985	13.75657
1990	12.49394
1995	9.58829
2000	8.47687
2005	6.53209
2010	5.21052
2015	5.14141
2020	4.47772
2025	4.13586
2030	4.13468
2035	4.2403
2040	4.25124
2045	4.13756
2050	4.01974
2055	3.98826
2060	4.02226
2065	4.07989
2070	4.11238
2075	4.12482
2080	4.12264
2085	4.14601
2090	4.18921
2095	4.24081
2100	4.28527