The Paste Special feature on Excel's Edit menu can save signficant time. For instance, you can convert a column of numbers with implied decimals, e.g. 1000 to whole numbers, 10.00. To do so, enter 100 in a worksheet cell, and then copy that cell to the clipboard (Edit, Copy is one way). Next, highlight the cells that you want to divide by 100, and then choose Edit, Paste Special, Divide, and then click OK. You can also use Paste Special to perform multiplication, addition, or subtraction.