How to hide x-axis values with function module STAT_GRAPH?

Question

I need to hide all the values in x-axis because they are worthless for the customer and don't want to watch them anymore.

I am talking about this:

Graphic generated with SAP tools

How you can see, in x-axis I squared the values I don't want to show anymore. I dont know how to use the function module for this purpouse but this is the code:

CALL FUNCTION 'STAT_GRAPH'
 EXPORTING
 ttext = 'Partograma'
 utext = 'Dilatacion, Estacion, Normal dilatacion, Normal estacion , Base '
 x_art = 'LIN'
 y_art = 'LIN'
 scale = 'MAN'
 xrngl = x1
 xrngu = x2
 yrngl = y1
 yrngu = y2
 xtcks = xt
 ytcks = '12'
 clr_fgrd = '1'
 winid = 'STAT1'
 TABLES
 opts = lt_opts
 data = lt_data.

I tried to change the parameters of function module STAT_GRAPH but with no success.

parameters

Any ideas?