var/run/OBSERROR_GPSEPH.TBL

   1 level,    height,        error (%)
   2 2       0.583861        1.001363687
   3 3       0.699247        0.97868234
   4 4       0.828886        0.956000993
   5 5       0.973136        0.933319646
   6 6       1.137158        0.910638299
   7 7       1.321746        0.887956952
   8 8       1.523315        0.862070876
   9 9       1.74769         0.817310233
  10 10      2.001154        0.785186649
  11 11      2.28562         0.761447327
  12 12      2.603658        0.749606762
  13 13      2.958331        0.728550976
  14 14      3.353453        0.678748916
  15 15      3.799495        0.646161854
  16 16      4.296768        0.64277257
  17 17      4.852567        0.647252069
  18 18      5.482894        0.60454254
  19 19      6.186011        0.514221183
  20 20      6.977809        0.394462302
  21 21      7.867713        0.323853411
  22 22      8.872742        0.25121997
  23 23      10.010967       0.195111244
  24 24      11.220463       0.182301994
  25 25      12.462545       0.163483956
  26 26      13.732089       0.165158103
  27 27      15.051692       0.219995979
  28 28      16.479813       0.231698469
  29 29      18.075117       0.243699065