Pound signs (####) will display when the column isn't wide enough to display the numeric data.  To correct this:

  1. Select the column you need to widen
  2. In the Home tab, in the Cells subgroup, click Format
  3. Under Cell Size, click Column Width
  4. In the Column Width box, type the value you want.  This may be trial and error and you find the right width.

You can also change the column width to automatically fit the contents:

  1. Select the column
  2. In the Home tab, in the Cells subgroup, click Format
  3. Under Cell Size, click AutoFit Column Width

Lastly, you can use a shortcut to widen your column to the necessary size:

  1. Once the data has been entered into a cell, hover your cursor over the line separating the alphabetical column heading of the column needing widening and the one to the right until the cursor changes to a cross bar with horizontal arrows
  2. Double click and the column will automatically widen