fiducial cells

The column numbers immediately below the ID cell are displayed in cells called fiducial cells. Fiducial cells are points accepted as fixed bases of reference. Marks are indicating the order in which each reading or sample reading was taken.

These cells contain integers, times, dates or other values, called fiducials, which provide a unique reference for each row of data values in the spreadsheet. The fiducial numbering scheme depends on the type of data contained in the database.