Year Percent change (Units) 1993 -14.200 1994 -22.900 1995 -12.200 1996 -10.000 1997 -3.000 1998 -1.900 1999 -0.200 2000 5.900 2001 8.800 2002 5.300 2003 9.500 2004 11.800 2005 3.100 2006 7.600 2007 8.200 2008 2.200 2009 -15.100 2010 4.100 2011 5.460 2012 0.224 2013 0.002 2014 -6.575 2015 -9.788 2016 2.417 2017 2.360 2018 3.488 2019 3.199 2020 -3.753 2021 3.446 2022 -29.079 2023 5.003 2024 3.202 2025 6.465 2026 4.994 2027 4.502 2028 4.300 2029 4.200