The AutoSum button on the Standard toolbar is one of the most useful tools in Excel. AutoSum automatically totals a range of values. Click into the cell where you want the total to appear and click the AutoSum button. The SUM formula appears in the cell and a marquee surrounds the range of values in the column. Click the AutoSum button again. A total of the range in the column directly appears in the last cell.
AutoSum can total cells in a row, as well as a column. Click the first empty cell in a row that contains values and click AutoSum, as illustrated in Figure 5.8. The SUM formula appears in the cell and a marquee surrounds the range of values in the row. Click the AutoSum button again. The total of the preceding cells appears in the last cell.
Figure 5.8. Using AutoSum to total cells in a row.
AutoSum adds ranges that contain values. If an empty cell appears in the column or row, AutoSum does not add cells that appear before the blank one.