ALV underline

Hi guys. I was just wondering if there is a way for me to segregate records in ALV using an underline.

For instance, if I have 3 records

LIFNR MATNR

C1000 12345

C1000 12345

C1000 12222

C1000 12222

C1001 12222

Its should display in alv like:

C1000 12345

C1000 12345

-

<--- underline since new matnr

C1000 12222

C1000 12222

-

<--- underline since new vendor

C1001 12222

please help. Thanks.