Year Percent change 1980 2 1981 4.2 1982 17.695 1983 28.198 1984 30.044 1985 30.785 1986 40.491 1987 164.115 1988 58.507 1989 42.076 1990 43.723 1991 33.258 1992 45.076 1993 42.255 1994 63.123 1995 47.668 1996 48.491 1997 7.36 1998 1.487 1999 2.874 2000 12.713 2001 9.061 2002 16.769 2003 13.455 2004 12.634 2005 6.428 2006 13.245 2007 8.161 2008 14.503 2009 3.789 2010 12.426 2011 11.167 2012 2.602 2013 4.261 2014 2.56 2015 3.551 2016 19.853 2017 15.113 2018 3.911 2019 4.167 2020 5.501 2021 5.501 2022 5.501 2023 5.501 2024 5.501