This has been discussed before. You can read about it here:
http://groups.google.com/groups?q=infopath+repeating+column&start &hl=en&lr=&ie=UTF-8&selm=%23zpUyKM9DHA.2472%40TK2MSFTNGP09.phx.gbl&rnum(

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Greg Collins [InfoPath MVP]
Please visit: http://www.InfoPathDev.com
In a repeating table, is it possible for the columns to repeat rather than
rows repeating? Or both at the same time?
If so, since there's a limited amount of space width wise, can the column on
the far left be dropped from the form?
Thanks
Ryan Graham