Year Percent change (Units) 1995 -7.032 1996 0.000 1997 1.513 1998 4.247 1999 -1.287 2000 3.348 2001 9.395 2002 -0.935 2003 4.635 2004 3.281 2005 7.196 2006 1.731 2007 2.200 2008 7.400 2009 2.177 2010 6.686 2011 4.855 2012 0.984 2013 2.163 2014 -0.937 2015 2.688 2016 -1.417 2017 1.420 2018 0.645 2019 6.253 2020 -4.773 2021 7.071 2022 20.620 2023 -1.988 2024 3.328 2025 1.855 2026 2.028 2027 1.902 2028 1.902 2029 1.902