Ticket closing delay means the average time taken by support agents to close the ticket. This is an important report for you to understand how your agents are performing and how much average time is required to close the ticket.
There is an option to choose duration like last 30 days, this week, last quarter, etc. Also, you can generate reports for custom dates where you can select particular days. If you want to generate a report for tickets of a specific category, priority, status, or any based on any other custom fields or default fields then you can use a custom filter. The custom filter allows you to set multiple conditions based on ticket fields.