Unfortunately the updating of a formula such as =TODAY() is not enough to trigger some VBA code. It has to be a "physical" change such as entering the date manually.
However, you could use the workbook open event to accomplish this. Try the below in the ThisWorkbook module and it will run when the file opens.
You could add to the code so it only runs the first time the file is opened. i.e. only run this piece of code if there's not already a figure against today's date.
This may not work for you, but there's too little information to work with to know for sure.
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