Year	Measure
1971	0.00048
1972	0.00139
1973	0.00146
1974	0.00215
1975	0.00288
1976	0.00279
1977	0.00248
1978	0.003
1979	0.003
1980	0.00333
1981	0.00368
1982	0.00349
1983	0.00278
1984	0.00275
1985	0.0029
1986	0.00418
1987	0.00411
1988	0.00493
1989	0.005
1990	0.00551
1991	0.00392
1992	0.00372
1993	0.00311
1994	0.00259
1995	0.00276
1996	0.00291
1997	0.0021
1998	0.00315
1999	0.0041
2000	0.00281
2001	0.00277
2002	0.0025
2003	0.00242
2004	0.00243
2005	0.00244
2006	0.00246
2007	0.00138
2008	0.0016
2009	0.0018
2010	0.00152