Excel 2003
Shortcut for entering current date and time
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Subtotals
Excel custom number formats (23.5K or 125.4M)
Creating a Pivot table column showing percentage of column
Reordering columns in Excel using horizontal sort
Copying data into multiple cells
Creating a custom user-defined chart type
Navigating a workbook/worksheet
Using styles in Excel 2003
Excel 2007
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