\begin{filecontents*}{GDP.csv}
Jahr,Total,Jung,Mittel,Alt
1990-01-01,2.5,4.9,2.2,1.6
1991-01-01,4.3,9.9,3.2,3.1
1992-01-01,5.3,10.0,4.3,4.4
1993-01-01,5.3,11.5,4.2,4.0
1994-01-01,4.9,11.0,3.7,3.5
1995-01-01,3.7,8.4,2.6,3.7
1996-01-01,3.9,7.7,3.0,3.7
1997-01-01,2.7,6.0,2.1,2.0
1998-01-01,2.0,4.4,1.4,2.0
1999-01-01,2.3,4.7,1.7,2.0
2000-01-01,2.3,4.8,1.7,1.6
2001-01-01,3.3,7.2,2.7,1.9
2002-01-01,3.3,8.2,2.5,1.9
2003-01-01,3.1,8.1,2.0,2.5
2004-01-01,2.6,7.2,1.7,1.3
2005-01-01,2.9,8.2,1.8,1.5
2006-01-01,2.3,7.1,1.3,1.1
2007-01-01,3.0,8.2,2.0,1.6
2008-01-01,7.2,16.0,6.1,3.4
2009-01-01,7.6,16.2,6.3,4.2
2010-01-01,7.1,14.6,5.6,5.2
2011-01-01,6.0,13.6,4.6,4.1
2012-01-01,5.4,10.7,4.6,3.2
2013-01-01,5.0,10.0,4.3,2.8
2014-01-01,4.0,8.7,3.2,2.6
2015-01-01,3.0,6.5,2.5,1.8
2016-01-01,2.5,4.9,2.2,1.6
\end{filecontents*}
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