Hello - whilst Excel has many preloaded cell formats more often than not there is a requirement to create your own. The custom category in the 'Format Cells' box is very useful for creating both date and number formats. I'm always surprised at the amount of Excel users who are unaware of this feature. The custom box allows you to create your own formats which can add that final touch to a report. Please note any formats created are saved with the spreadsheet only.
Below are some examples of some custom date and number formats.
Please feel free to download the example above. I hope you find this post useful.