Year	Measure
1971	0.00055
1972	0.00046
1973	0.00069
1974	0.00072
1975	0.00076
1976	0.00068
1977	0.00068
1978	0.00083
1979	0.00084
1980	0.00077
1981	0.00091
1982	0.00072
1983	0.00097
1984	0.00111
1985	0.00153
1986	0.00252
1987	0.00219
1988	0.00255
1989	0.00317
1990	0.00266
1991	0.00304
1992	0.00398
1993	0.0035
1994	0.00267
1995	0.00325
1996	0.00347
1997	0.00214
1998	0.004
1999	0.00384
2000	0.00404
2001	0.00464
2002	0.0039
2003	0.00353
2004	0.0037
2005	0.00406
2006	0.0036
2007	0.00417
2008	0.00422
2009	0.00412
2010	0.00634