Excel automatically removes leading zeros from numbers, which can be frustrating when you're trying to enter numbers with leading zeros, like bus numbers. However, there is a simple solution to this problem.

To get Excel to leave a zero in front of a number, you need to format the cell as text. Here's how to do it:

1. Select the cell or cells where you want to enter the bus numbers.
2. Right-click on the selected cells and choose "Format Cells" from the context menu.
3. In the Format Cells dialog box, click on the "Number" tab.
4. In the Category list, select "Text".
5. Click "OK" to close the dialog box.

Now, when you enter the bus numbers, Excel will treat them as text and leave the leading zero intact. If you've already entered the bus numbers without the leading zero, you can simply add the zero in front of the number and Excel will automatically treat it as text.

I hope this helps you with your bus number list!