1980 4,056 2,184

1981 3,983 2,520

1982 4,356 2,853

1983 4,865 3,309

1984 5,463 3,738

1985 5,834 4,116

1986 6,570 4,624

1987 7,511 5,281

1988 8,300 6,056

1989 9,283 6,668

1990 10,048 7,519

1991 11,139 8,489

1992 12,221 9,123

1993 13,240 9,879

1994 14,410 10,908

1995 15,535 12,079

1996 16,664 13,108

1997 17,806 13,990

1998 18,598 13,272

1999 20,002 14,892

2000 21,590 16,452

2001 21,679 17,459

2002 23,120 18,939

2003 24,462 19,785

2004 26,670 21,245

2005 28,915 22,742

2006 31,333 24,535

2007 34,141 26,440

2008 34,936 27,523

2009 34,526 27,796

2010 38,593 29,825

2011 40,777 31,327

2012 42,201 32,474

2013 43,678 33,791

2014 45,854 35,277