Year Percent change (Units) 1993 -8.700 1994 -12.700 1995 -4.100 1996 -3.581 1997 1.376 1998 -5.319 1999 6.347 2000 10.054 2001 5.082 2002 4.746 2003 7.356 2004 7.145 2005 6.397 2006 8.165 2007 8.550 2008 5.247 2009 -7.821 2010 4.512 2011 3.876 2012 4.024 2013 1.755 2014 0.736 2015 -1.973 2016 0.194 2017 1.827 2018 2.806 2019 2.198 2020 -2.654 2021 5.988 2022 -1.201 2023 3.585 2024 3.163 2025 1.811 2026 1.250 2027 1.250 2028 1.250 2029 1.250