AutoFilling Numbers with a Trailing Period

Iana wants to AutoFill a column of sequential numbers as "1.", "2.", etc., through "150.". The AutoFill will only work without the trailing period, but she wants the period there.

As Iana has discovered, AutoFill doesn't do a great job on figuring out how to "increment" text. It does OK if you are working with well-established sequences, such as the alphabet or days of the week, but it is downright stupid when it comes to most other text values. And, unfortunately, entering a number (1) followed by a period places a text string (1.) in the cell. Bingo! AutoFill chokes.

There are at least three potential solutions. The first is to stick to numbers (which AutoFill can work with) and apply a custom format to the cells in order to add the period. Follow these steps:

1. Use AutoFill to create your sequence of 150 cells, numbered 1 through 150.
2. Select the cells.
3. Select the Home tab of the ribbon.
4. Click the small icon at the bottom-right of the Number group. Excel displays the Format Cells dialog box.
5. If the Number tab is not displayed, select it.
6. In the Category list, choose Custom. The dialog box changes so you can enter a custom format. (See Figure 1.)



Figure 1. The Number tab of the Format Cells dialog box.

7. In the Type box enter the following: 0"." (the digit 0 followed by a period enclosed within quote marks).
8. Click OK.

Your numbers should now all appear just fine with a trailing period. And, best of all, they are still numbers so you could do math with them, if necessary.

A couple of ExcelTips subscribers suggested a second method to get sequential numbers with a trailing period. This method uses a formula and results in numbers without applying a custom format to the cells. Follow these steps:

1. In cell A1 enter the following formula:

       =Row(A1)&"."

2. Use AutoFill to create your sequence of 150 cells, numbered 1 through 150 which are automatically followed by periods.

Another approach is to go ahead and expect that your numbers will end up as text. In this case, you should make sure that columns A and B are empty and then follow these steps:

1. In column A, use AutoFill to create your sequence of 150 cells, numbered 1 through 150.
2. In cell B1 (or whatever cell is to the right of the first cell in the column A sequence) enter the following formula:

       =A1 & "."

3. With cell B1 still selected, double-click the fill handle at the bottom-right corner of the cell. You should now have a range of cells in column B that have your 1 through 150 numbers with the trailing period.
4. Make sure the range of cells are selected in column B. (For instance, select the range B1:B150 if those contain your numbers followed by periods.)
5. Press Ctrl+C to copy the range to the Clipboard.
6. Display the Home tab of the ribbon.
7. Click the down-arrow under the Paste tool and select to paste Values.
8. Delete column A.

Your numbers should now all appear just fine, with the trailing period, in column A. The difference between this approach and the earlier approach is that in this case the numbers aren't really numbers in the eyes of Excel—they are text values.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (13294) applies to Microsoft Excel 2007, 2010, 2013, 2016, 2019, and Excel in Microsoft 365.