Year	Measure
1971	0.00518
1972	0.00504
1973	0.0058
1974	0.00536
1975	0.00547
1976	0.00662
1977	0.00611
1978	0.0085
1979	0.00909
1980	0.00931
1981	0.00934
1982	0.0095
1983	0.01096
1984	0.01195
1985	0.01102
1986	0.01202
1987	0.01285
1988	0.01362
1989	0.01343
1990	0.01301
1991	0.01369
1992	0.01538
1993	0.01381
1994	0.01583
1995	0.01567
1996	0.01372
1997	0.01413
1998	0.01401
1999	0.01174
2000	0.01023
2001	0.01104
2002	0.01278
2003	0.01513
2004	0.01416
2005	0.01673
2006	0.01701
2007	0.01501
2008	0.01427
2009	0.01417
2010	0.01576