Year Percent change (Units) 1993 109.200 1994 35.900 1995 25.000 1996 17.600 1997 8.074 1998 4.295 1999 2.114 2000 2.633 2001 2.526 2002 1.963 2003 2.940 2004 6.187 2005 6.890 2006 6.571 2007 10.081 2008 15.253 2009 3.259 2010 -1.224 2011 4.222 2012 2.285 2013 0.011 2014 0.690 2015 0.213 2016 0.099 2017 2.894 2018 2.554 2019 2.747 2020 0.081 2021 3.239 2022 17.245 2023 9.058 2024 1.954 2025 3.611 2026 2.199 2027 2.250 2028 2.261 2029 2.318