Year	Measure
1971	0.02807
1972	0.03115
1973	0.03528
1974	0.03618
1975	0.03422
1976	0.03547
1977	0.03671
1978	0.03058
1979	0.03734
1980	0.04153
1981	0.04084
1982	0.03655
1983	0.0182
1984	0.01241
1985	0.01995
1986	0.02835
1987	0.02948
1988	0.02951
1989	0.03125
1990	0.03325
1991	0.03452
1992	0.03626
1993	0.03359
1994	0.03159
1995	0.03084
1996	0.03268
1997	0.03299
1998	0.01801
1999	0.02375
2000	0.02966
2001	0.02894
2002	0.02153
2003	0.01621
2004	0.0215
2005	0.02237
2006	0.02179
2007	0.01411
2008	0.0229
2009	0.02482
2010	0.02466