1. Highlight the range of cells or rows or columns that you want to format.
2. Choose Format, Conditional Formatting to display the Conditional Formatting dialog box.
3. Select Formula Is from the first drop-down list box, and enter =MOD(ROW(),2)=0 in the
    second box.
4. Click the Format button to bring up the Format Cells dialog box.
    Select the Patterns tab and specify a color for the shaded rows. You'll probably want to
    choose a light color, so that the default black text will still be legible. Or, you can go all out 
    and change the text color as well (do this in the Font tab of the Format Cells dialog box). 
    For example, you might select a dark blue background, accompanied by a mellow yellow
    text color.
5. Click OK twice to return to your worksheet.

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