Year Cubic Meters 1990 15756000 1991 15252000 1992 16953000 1993 18877000 1994 16845000 1995 19279000 1996 19411000 1997 18050000 1998 17668000 1999 16608300 2000 15939300 2001 15337200 2002 16122000 2003 15810000 2004 16503000 2005 16185000 2006 18084000 2007 18319000 2008 19420000 2009 19300000 2010 20554000 2011 21039000