Year Total 1990 0 1992 0 1993 0 1994 0 2000 7076 2001 175941 2002 251602 2003 264091 2004 436628 2005 567584 2006 821800 2007 1021481 2008 1314406 2009 1800000 2010 2603582 2011 2884964 2012 3134700 2013 3190233 2014 3197550 2015 3531000 2016 3713190 2017 4135363