In this example, the goal is to return the sum for an entire row in an Excel worksheet. One way to do this is to use a full row reference.
Full row references
Excel supports full row references like this:
=SUM(1:1) // sum all of row 1 =SUM(3:3) // sum all of row 2 =SUM(4:5) // sum all of rows 4 and 5
You can see how this works yourself by typing 1:1 or 3:3 into the name box (left of the formula bar) and hitting return. You will see Excel select the entire row.
To solve the problem in the example worksheet, we can use a full row reference to row 5 with the SUM function like this:
The result is the sum of all numeric values in row 5. As the formula is copied down, we get a sum for row 6 and row 7 as well:
=SUM(5:5) // sum red =SUM(6:6) // sum blue =SUM(7:7) // sum green
As new entries for "Red" are added to the table in rows 5, 6, and 7, the formula will automatically include these new amounts.
Advantages and risks
The main advantage to full row references is simplicity. Simple and very compact, a full row reference will automatically include all data in a row, even when data is added or removed. However, full row references come with certain risks. One risk is that you may accidentally include extra data in a calculation. For example, if you use =SUM(5:5) to sum numbers in row 5, you are targeting over 16,000 cells to the right. If row 5 includes extra dates somewhere far to the right, the numeric values of these dates will be included, and SUM will return an incorrect result.