Currently, Zendesk only provides default metrics for counting the age of unsolved tickets during calendar days. This article https://support.zendesk.com/hc/en-us/articles/4408825749786-Explore-recipe-Filtering-reports-by-business-hours can only look at the number of tickets received during business hours. However, that metric doesn't count the age of the business days and is still not enough for me.
I hope you can customize more on this for business days. It's almost the same but only counts the calendar days:
(IF ([Ticket status - Unsorted] != "Solved" AND [Ticket status - Unsorted] != "Closed")
THEN DATE_DIFF(NOW(), [Ticket created - Timestamp], "nb_of_days")
ENDIF)
We need to see how many business days for unsolved tickets. We have to report it to our regulator per 3 months. All this time, we are so manual in excel, and it's so unpractical with time and effort, especially when dealing with thousands of tickets. Hope to hear the good news asap. Thanks!

