XLReporter hide repetitive field

Does anyone know how to hide repetitive fields in XLReporter ? For example I want my report to look like this ;

Product group Item Number Whse code Qty on hand

-

GROUP1 A0001 01 25

A0002 02 10

A0004 01 10

GROUP2 B7778 01 5

A0002 02 2

.

.

.

Currently my report repeats the group code on each line.

Thank in advance