$DATA << EOD
2000 ?   ?   9.1
2001 ?   ?   9.2
2002 ?   ?   9.2
2003 9.1 9.1 9.1
2004 9.3 9.2 9.0
2005 9.4 9.2 9.0
2006 9.5 9.3 8.9
2007 9.6 9.2 8.9
2008 9.7 9.2 8.8
2009 9.8 9.1 8.7
2010 9.9 9.0 8.5
2011 9.9 8.9 8.5
2012 9.8 8.9 8.6
2013 9.7 8.8 ?
2014 9.6 8.7 ?
2015 9.6 8.6 8.8
2016 9.5 8.5 8.8
2017 9.5 8.4 8.9
2018 9.6 8.4 ?
2019 9.5 8.2 ?
2020 9.4 8.3 ?
EOD
set term 'pngcairo' font 'Arial,10'
set output 'rm076.png'
set xrange [1999:2021]
set xtics offset -2, -1.0 rotate by 30 1
set title 'Indikator i mit Element e aus Aggregation a ex-post Prognose P'
plot \
$DATA using 1:2 title 'P1' with linespoints,\
$DATA using 1:3 title 'P2' with linespoints,\
$DATA using 1:4 title 'echt' with linespoints
#pause mouse