Year	Measure
1971	0.00088
1972	0.00088
1973	0.00091
1974	0.00093
1975	0.00091
1976	0.00093
1977	0.00095
1978	0.00102
1979	0.00109
1980	0.00118
1981	0.0012
1982	0.00134
1983	0.00141
1984	0.00149
1985	0.00141
1986	0.00145
1987	0.00142
1988	0.00135
1989	0.00133
1990	0.00189
1991	0.00186
1992	0.00191
1993	0.00203
1994	0.00211
1995	0.00215
1996	0.00221
1997	0.00223
1998	0.00218
1999	0.00216
2000	0.00216
2001	0.00254
2002	0.00252
2003	0.00277
2004	0.00299
2005	0.00328
2006	0.00369
2007	0.00375
2008	0.00357
2009	0.00373
2010	0.00511