Year Percent change (Units) 1994 47.656 1995 29.003 1996 19.742 1997 9.311 1998 8.782 1999 3.098 2000 3.932 2001 5.626 2002 3.588 2003 1.387 2004 3.038 2005 4.117 2006 4.444 2007 6.745 2008 10.606 2009 0.199 2010 2.741 2011 5.080 2012 4.219 2013 3.247 2014 0.476 2015 0.068 2016 0.800 2017 3.651 2018 3.412 2019 2.268 2020 -0.634 2021 4.487 2022 19.447 2023 9.116 2024 4.159 2025 2.486 2026 2.510 2027 2.510 2028 2.510 2029 2.510