Year Number 1996 1.32520198822021 1998 1.42638552188873 2000 1.58620870113373 2002 1.59826338291168 2003 1.547776222229 2004 1.31764233112335 2005 1.38035714626312 2006 1.23125755786896 2007 1.26963186264038 2008 1.27317667007446 2009 1.24936008453369 2010 1.25345623493195 2011 1.06393671035767 2012 1.06507515907288 2013 1.04275786876678 2014 1.12549698352814 2015 1.05367743968964 2016 1.06645977497101 2017 1.23830723762512 2018 1.27142131328583 2019 1.0135281085968 2020 0.998400986194611 2021 0.887379705905914 2022 0.913422584533691