Hi  Carlos and Jack, 

Carlos, I guess you refer to this kind of format? the background and the labels? I have in some part of my hard drive the code to modify the background in gnuplot. let me find it

Something like this, perhaps?

<hansl>

open denmark
list X = IBO IDE
plot X
    options with-lines time-series
    # to draw a background for the plot area only
    literal set object 1 rect from graph 0,0 to graph 1,1 fillcolor "0xfdecba" behind
    # or alternatively, for the whole thing
    # literal set object 1 rect from screen 0,0 to screen 1,1 fillcolor "0xfdecba" behind
end plot --output=display

</hansl>

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  Riccardo (Jack) Lucchetti
  Dipartimento di Scienze Economiche e Sociali (DiSES)

  Università Politecnica delle Marche
  (formerly known as Università di Ancona)

  r.lucchetti@univpm.it
  http://www2.econ.univpm.it/servizi/hpp/lucchetti
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