Year Percent 1990 3.13 1991 3.131 1992 3.127 1993 3.12 1994 3.113 1995 3.108 1996 3.107 1997 3.108 1998 3.11 1999 3.111 2000 3.112 2001 3.112 2002 3.113 2003 3.113 2004 3.114 2005 3.533 2006 3.406 2007 3.276 2008 3.159 2009 3.221 2010 3.203 2011 3.181 2012 3.199 2013 3.146 2014 3.12 2015 3.055 2016 2.996 2017 2.999 2018 3.002 2019 3.005 2020 3.009 2021 3.012 2022 3.015 2023 3.018 2024 3.021 2025 3.025 2026 3.028 2027 3.031 2028 3.034 2029 3.037 2030 3.041