How to - when a new item is created in board, +1 ticket number and assign it to the new item

One of my boards is used as a bug tracking system. Each item is considered a ticket, or change request.
I have a number column where we manually input the ticket number, in the format CR2020-xxxx. So CR2020-0001, CR2020-0002, etc. Every time a new ticket is created, we look at the last number, and +1.
As the board increases, and the “Done” tasks get moved, it’s getting trickier to know which is the next number. Even more so if 2 people are doing that at the same time. So I’m hoping to find some automated way to, whenever a new item is created in this board, auto-populate that value.
Does anyone know a way to do that? Maybe using a formula column?
Or any other creative solution to this problem? Pining a fake item at the top, where I keep the new number available, or something?

Hey @cquad, I wonder if you’ve checked out the item ID column for this! Let me know what you think :slight_smile:

It can even then be added to or changed using the formula column, with letters or functions such as concatenate.

I did try the Id column. But it showed me gigantic numbers, and I couldn’t find an option to customize it. So now you’re telling me that I have to use 2 columns to be able to achieve this?
Can you show me an example of such a formula?