conditional formating or macro???

OK i have a spreadsheet between 6 and 10 thousand lines long. I need to be able to alternately color sets of rows based on the data in the first column. This column is actually barcode numbers. example is like this. I need rows with data of 1 white, 2 gray, 3 white and so on. The barcodes are forever changeing and may not be listed twice. Is there a way to do this? Sensetive data so i can not post document.

(white)1 asdf a
(white)1 qwer a
(white)1 zxcv a
(white)1 asdf a
(white)1 qwer a
( gray)2 asdf b
( gray)2 qwer b
( gray)2 zxcv b
(white)3 asdf c
(white)3 qwer c
(white)3 zxcv c
(white)3 asdf c
( gray)4 asdf d
(white)5 asdf e
(white)5 qwer e

Have a look here: Colour Banding for some ideas.

You would only enter the formula in the helper column once, then copy it down the column, simply by double-clicking the little black box at bottom right corner of first cell with formula...

Then you would apply the conditional formatting...

...but if you want a macro, then probably someone else can help.

You can also go through this thread I was involved in a while ago at another forum.... it has several alternatives with code or with/without helpers, etc...

http://www.mrexcel.com/forum/showthread.php?t=174759

Ok i was misunderstanding. Makes sense now. The only thing is im not sure how to add the specific conditional formation your specified in excel 2007. Im new to 2007 and the tabbed functions are still a little confusing.

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