Year | Value | 2021 | 24.226045544488 | 2020 | 24.109031760405 | 2019 | 23.992017976322 | 2018 | 23.875004192239 | 2017 | 23.758023946071 | 2016 | 23.641010161988 | 2015 | 23.523996377905 | 2014 | 23.406996008988 | 2013 | 23.289995640071 | 2012 | 23.172995271154 | 2011 | 23.055994902237 | 2010 | 22.93899453332 | 2009 | 23.096468457591 | 2008 | 23.253942381863 | 2007 | 23.411416306134 | 2006 | 23.568890230406 | 2005 | 23.726364154677 | 2004 | 23.883838078948 | 2003 | 24.04131200322 | 2002 | 24.198785927491 | 2001 | 24.356259851762 | 2000 | 24.513733776034 | 1999 | 24.671211054097 | 1998 | 24.82868833216 | 1997 | 24.986165610222 | 1996 | 25.143642888285 | 1995 | 25.301120166348 | 1994 | 25.458597444411 | 1993 | 25.616074722474 | 1992 | 25.773552000537 | 1991 | 25.931029278599 | 1990 | 26.088506556662 |
|