Year	Measure
1971	0.00067
1972	0.00078
1973	0.00021
1974	0.00389
1975	0.00855
1976	0.01356
1977	0.01886
1978	0.02163
1979	0.02348
1980	0.02472
1981	0.02479
1982	0.02665
1983	0.02437
1984	0.02794
1985	0.02717
1986	0.02252
1987	0.02183
1988	0.02085
1989	0.01992
1990	0.01903
1991	0.01819
1992	0.01738
1993	0.01661
1994	0.01589
1995	0.01523
1996	0.0151
1997	0.01505
1998	0.01527
1999	0.01502
2000	0.01738
2001	0.01782
2002	0.01242
2003	0.01356
2004	0.01994
2005	0.02012
2006	0.01793
2007	0.01548
2008	0.01253
2009	0.008
2010	0.01092