Year Number 1995 3753000 1996 3684000 1997 3908000 1998 4250000 1999 4660000 2000 5322000 2001 5147000 2002 5347000 2003 4753000 2004 5818000 2005 6023000 2006 6155000 2007 6448000 2008 6891000 2009 7818000 2010 8798000 2011 9795000 2012 11140000 2013 12176000 2014 14202000 2015 13232000 2016 17242000 2017 13336000 2018 15347000 2019 17503000 2020 2519000