Thank you very much!
I compose commands for gnuplot in the following way (it is all a single line): 
plot $years $yscala "$abc_this_01" title "" with errorbars lt rgb "$co
+lor_abc" lw 2, "$abc_this_01" title "{/Helvetica=10 ABC_Stuff}" with 
+lines lt rgb "$color_abc" lw 3,"$def_this_01" title "" with errorbars
+ lt rgb "$color_def" lw 2, "$def_this_01" title "{/Helvetica=10 DEF_S
+tuff}" with lines lt rgb "$color_def" lw 3, "$ghi_this_01" title "" w
+ith errorbars lt rgb "$color_ghi" lw 2, "$ghi_this_01" title "{/Helve
+tica=10 GHI_Stuff}" with lines lt rgb "$color_ghi" lw 3, "$jkl_this_0
+1" title "" with errorbars lt rgb "$color_jkl" lw 2, "$jkl_this_01" t
+itle "{/Helvetica=10 JKL_Stuff}" with lines lt rgb "$color_jkl" lw 5,
+ "$mno_this_01" with steps lt 1 lw 5 title "{/Helvetica=10 Abnormalit
+y Border}"

[download]
and the files looks like this: 
# Value Low High
2006 78.6 76.5 80.6
2007 86.3 84.7 87.6
2008 92.7 92.3 93.1
2009 95.3 94.9 95.6
2010 96.8 96.5 97.1
2011 97.0 96.5 97.5

[download]
It plots diagramms with the values (plus y-errorbars) from four sources (abc, def ...) and with the abnormality border. There are ca. 20 topics ("this", "that" etc.) with up to 8 subgroups (01, 02 etc.).
I have indeed the feeling that the composition is somehow ugly. Leastwise it works :-)
However I would be very glad for any suggestion how I could organize the data better.
Thanks again.
VE

In reply to Re^2: How to declare variables per loop by Anonymous Monk
in thread How to declare variables per loop by Anonymous Monk

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