Year % change from 1990 1991 1.11221559797536 1992 -0.550692336759906 1993 0.129971093466064 1994 5.15118767103835 1995 7.81872402082426 1996 15.1688300435403 1997 15.1579991190848 1998 7.57466718976021 1999 18.4616717652241 2000 20.129874818582 2001 22.5916236037133 2002 20.7482002613863 2003 22.4667069416598 2004 25.4959961682596 2005 27.9808509255627 2006 30.0031048650106 2007 33.0930472685612 2008 35.6946353227736 2009 37.7195368215329 2010 34.9022930270509 2011 36.2513159573214 2012 37.6003388875919