Year % change from 1990 1991 0.60239518443761 1992 2.6714134467442 1993 -2.47751327908726 1994 -0.761654254856492 1995 -1.67431969983712 1996 -1.75080004438858 1997 8.13975808217289 1998 0.190750976998921 1999 -2.47796316346698 2000 -2.81522648679288 2001 -1.15095420476936 2002 1.81993227740471 2003 2.45037025484451 2004 6.29493220242399 2005 9.11060857359658 2006 14.2397403867206 2007 15.4319339929638 2008 14.6180931500604 2009 16.5938353843063 2010 17.2067278709372 2011 18.8753587005444 2012 20.1801121364476