Year Thousands of Persons 1990-01-01 25.8 1991-01-01 25.3 1992-01-01 26.7 1993-01-01 28.0 1994-01-01 29.2 1995-01-01 29.8 1996-01-01 29.1 1997-01-01 28.3 1998-01-01 28.6 1999-01-01 29.0 2000-01-01 29.6 2001-01-01 29.9 2002-01-01 31.8 2003-01-01 32.4 2004-01-01 32.6 2005-01-01 32.7 2006-01-01 31.6 2007-01-01 29.1 2008-01-01 26.5 2009-01-01 23.6 2010-01-01 21.6 2011-01-01 20.4 2012-01-01 19.4 2013-01-01 18.8 2014-01-01 17.8 2015-01-01 17.5 2016-01-01 17.3 2017-01-01 16.6