year r Error 1993 0.0246 0.0072 1994 0.0255 0.0042 1995 0.0262 0.0027 1996 0.0243 0.0027 1997 0.0154 0.0057 1998 0.0116 0.0099 1999 0.0238 0.0162 2000 0.0194 0.0135 2001 0.0201 0.0126 2002 0.0464 0.0132 2003 0.0596 0.0153 2004 0.0519 0.0159 2005 0.0408 0.0177 2006 0.0245 0.0195