R version 2.15.2 (2012-10-26) -- "Trick or Treat"
Copyright (C) 2012 The R Foundation for Statistical Computing
ISBN 3-900051-07-0
Platform: i686-pc-linux-gnu (32-bit)

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> x <- c(14.544,14.931,14.886,16.005,17.064,15.168,16.050,15.839,15.137,14.954,15.648,15.305,15.579,16.348,15.928,16.171,15.937,15.713,15.594,15.683,16.438,17.032,17.696,17.745,19.394,20.148,20.108,18.584,18.441,18.391,19.178,18.079,18.483,19.644,19.195,19.650,20.830,23.595,22.937,21.814,21.928,21.777,21.383,21.467,22.052,22.680,24.320,24.977,25.204,25.739,26.434,27.525,30.695,32.436,30.160,30.236,31.293,31.077,32.226,33.865,32.810,32.242,32.700,32.819,33.947,34.148,35.261,39.506,41.591,39.148,41.216,40.225)
> par4 = '12'
> par3 = 'Goudkoers in EUR'
> par2 = 'NBB'
> par1 = 'Goudkoers in EUR'
> ylimmax = as.numeric(Maanden)
Error: object 'Maanden' not found
Execution halted