Excel 2007 : Highlight every other group of rows

[JimDandy]

I’m trying to take a table of duplicate information and highlight every other row with a light grey highlight just so it’s easier to see the individual groups. The duplicate data is sorted and in column A and the other columns will have varying bits of data. sometimes there are 2 duplicate values and sometimes there are 3, maybe even 4.

In the example below, the rows with 12345 data should be light gray along with the 98765 rows

12345	data1	data2	data3
12345	data3	data2	data1
54321	data1	data2	data3
54321	data4	data5	data6
54321	data7	data6	data5
98765	data1	data5	data2
98765	data3	data1	data8