Hi Andrew
I'm AnnaThomas and I'd happily help you with your question. In this Forum, we are Microsoft consumers just like yourself.
The DATEDIF function is available in any version of Excel, but it is not shown in the list of functions. You can simply type =DATEDIF( in a cell to use it.
The above is as suggested by Sergei Baklan in the thread below
Learn more: https://support.microsoft.com/office/25dba1a4-2812-480b-84dd-8b32a451b35c
I hope this helps ;-), let me know if this is contrary to what you need, I would still be helpful to answer more of your questions.
Best Regards,
AnnaThomas
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