Year Number of 1990 5127.93 1991 5273.23 1992 5504.71 1993 5743.71 1994 5839.15 1995 5776.06 1996 5629.65 1997 5489.99 1998 5347.46 1999 5169.17 2000 5163.92 2001 5126.62 2002 5097.29 2003 5044.29 2004 4992.34 2005 5011 2006 4980.4 2007 5049.39 2008 5161.99 2009 5182.85 2010 5273.85 2011 5337.71 2012 5404.44 2013 5548.41 2014 5715.58 2015 5970.57 2016 6182.27