Year Percent 1990 2.36673 1991 1.91463 1992 1.67481 1993 1.48708 1994 1.51553 1995 1.38823 1996 1.35359 1997 1.47178 1998 1.21464 1999 1.30175 2000 1.1218 2001 1.10314 2002 1.08919 2003 1.102 2004 1.03022 2005 1.92738 2006 0.64866 2007 0.75228 2008 0.7299 2009 1.01726 2010 0.93841 2011 0.93064 2012 0.96505 2013 0.95553 2014 0.94705 2015 0.90332 2016 0.86472 2017 0.83307 2018 0.83151 2019 0.81409 2020 0.88275