Year Percent change (Units) 1993 34.755 1994 26.362 1995 23.140 1996 13.118 1997 6.401 1998 2.697 1999 3.005 2000 1.743 2001 3.173 2002 1.451 2003 3.583 2004 7.334 2005 7.127 2006 6.740 2007 14.024 2008 10.398 2009 -1.367 2010 2.401 2011 3.879 2012 1.590 2013 -0.404 2014 0.274 2015 0.404 2016 2.105 2017 2.160 2018 2.549 2019 2.137 2020 -0.489 2021 7.883 2022 20.702 2023 0.854 2024 5.684 2025 2.013 2026 2.354 2027 2.165 2028 2.340 2029 2.300