Year Percent 1990 4.02 1991 4.12 1992 4.07 1993 4 1994 4.04 1995 4.24 1996 3.98 1997 3.86 1998 3.89 1999 3.84 2000 3.73 2001 3.52 2002 3.78 2003 4.01 2004 3.93 2005 3.86 2006 4.04 2007 4.45 2008 4.64 2009 4.4 2010 4.43 2011 4.23 2012 4.2 2013 4.38 2014 4.63 2015 4.64 2016 4.751 2017 4.79 2018 4.829 2019 4.868 2020 4.908 2021 4.947 2022 4.986 2023 5.025 2024 5.064 2025 5.103 2026 5.143 2027 5.182 2028 5.221 2029 5.26 2030 5.299