Year,F
1981,0.0173
1982,0.0231
1983,0.0229
1984,0.0266
1985,0.0241
1986,0.0231
1987,0.0193
1988,0.0200
1989,0.0187
1990,0.0205
1991,0.0172
1992,0.0184
1993,0.0153
1994,0.0141
1995,0.0119
1996,0.0115
1997,0.0105
1998,0.0104
1999,0.0114
2000,0.0120
2001,0.0142
2002,0.0166
2003,0.0187
2004,0.0199
2005,0.0192
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