Year Percent 1990 96.261 1991 96.223 1992 96.217 1993 96.029 1994 95.837 1995 95.64 1996 95.41 1997 95.159 1998 94.874 1999 94.545 2000 95.553 2001 95.144 2002 94.976 2003 94.605 2004 94.21 2005 93.803 2006 93.357 2007 94.045 2008 94.315 2009 94.459 2010 94.393 2011 94.307 2012 95.533 2013 96.534 2014 96.491 2015 96.399 2016 96.396 2017 96.421 2018 96.452 2019 96.487 2020 96.523 2021 96.514 2022 96.504 2023 96.501 2024 96.508 2025 96.526 2026 96.537 2027 96.549 2028 96.567 2029 96.595 2030 96.635