Year Percent change (Units) 1996 4.525 1997 -0.518 1998 -0.357 1999 1.384 2000 4.001 2001 3.043 2002 1.570 2003 3.584 2004 4.814 2005 6.602 2006 6.767 2007 5.570 2008 2.686 2009 -4.657 2010 2.435 2011 1.760 2012 -0.785 2013 -0.046 2014 2.262 2015 5.388 2016 2.537 2017 5.169 2018 3.220 2019 3.030 2020 -5.503 2021 3.553 2022 2.328 2023 -0.405 2024 0.656 2025 2.014 2026 2.101 2027 2.198 2028 2.251 2029 2.303